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2011Numericalsimulationso_省略_elowersolaratmo

Research in Astron.Astrophys.2011V ol.11No.2,225–236 https://www.wendangku.net/doc/aa1968599.html, https://www.wendangku.net/doc/aa1968599.html,/journals/raa R esearch in A stronomy and A strophysics

Numerical simulations of magnetic reconnection in the lower solar atmosphere?

Xiao-Yan Xu1,2,Cheng Fang2,Ming-De Ding2and Dan-Hui Gao2

1Purple Mountain Observatory,Chinese Academy of Science,Nanjing210008,China;

xyxu@https://www.wendangku.net/doc/aa1968599.html,

2Department of Astronomy,Nanjing University,Nanjing210093,China

Received2009November23;accepted2010July25

Abstract Observations indicate that Ellerman bombs(EBs)and chromospheric mi-

cro?ares both occur in the lower solar atmosphere,and share many common features,

such as temperature enhancements,accompanying jet-like mass motions,short life-

time,and so on.These strongly suggest that EBs and chromospheric micro?ares could

both probably be induced by magnetic reconnection in the lower solar atmosphere.

With gravity,ionization and radiation considered,we perform two-dimensional nu-

merical simulations of magnetic reconnection in the lower solar atmosphere.The in-

?uence of different parameters,such as intensity of the magnetic?eld and anomalous

resistivity,on the results are investigated.Our result demonstrates that the temperature

increases are mainly due to the joule dissipation caused by magnetic reconnection.

The spectral pro?les of EBs and chromospheric micro?ares are calculated with the

non-LTE radiative transfer theory and compared with observations.It is found that the

typical features of the two phenomena can be qualitatively reproduced.

Key words:Sun:chromosphere—Sun:photosphere—Sun:magnetic reconnection

—Sun:numerical simulation

1INTRODUCTION

Both Ellerman bombs(EBs)and chromospheric micro?ares are small short-lived solar eruptive events,which occur in the lower solar atmosphere,i.e.the photosphere and chromosphere.Owing to the simplicity of their structures,the study of the two phenomena can be very useful for understand-ing other eruptive processes and the mechanism of heating in the lower solar atmosphere.Recently, by using high resolution data,many authors investigated these processes in detail and found some new results on their properties and nature.

EBs,also well-known as moustaches,are small brightenings located in the lower solar chromo-sphere and upper photosphere.Observations indicate that the typical size of EBs is on the order of about one arcsecond(Zachariadis et al.1987;Kurokawa et al.1982;Denker1997;Dara et al.1997; Fang et al.2006a),and the typical lifetime is about10–20min(Kurokawa et al.1982;Nindos& Zirin1998;Qiu et al.2000;Fang et al.2006a).Kitai(1983)and Kurokawa et al.(1982)detected an upward motion in these events with a velocity of about several kilometers per second.Dara et al.

?Supported by the National Natural Science Foundation of China.

226X.Y.Xu et al.

(1997)found that a strong upward motion was related to strong EBs.On the other hand,Georgoulis et al.(2002)studied high spatial resolution data,which indicated that80%of the EBs they stud-ied showed downward photospheric motion at a velocity of0.1–0.4km s?1.Fang et al.(2006a) used high-resolution spectral data of14EBs observed by the French-Italian90cm vacuum tele-scope,THEMIS,and found that the excess intensity in the two wings of both Hαand Ca IIλ8542is asymmetric.According to the semi-empirical models given by Fang et al.(2006a),the temperature enhancement in the photosphere and the lower chromosphere is about600–1300K.The total energy of the EBs is1026–5×1027erg.

To explore the nature of EBs,it is important to study the relationship between EBs and ambient magnetic features.EBs are usually observed at the places close to sunspots or around strong magnetic structures(Zachariadis et al.1987;Dara et al.1997;Nindos&Zirin1998).It was found that more than half of the EBs are located at or close to the magnetic polarity inversion lines,and the others are at the boundaries of unipolar magnetic areas(Qiu et al.2000;Fang et al.2006a).Georgoulis et al.(2002)found that EBs occur in the magnetic separatrix or quasi-separatrix layer of the lower chromosphere.Denker et al.(1995)found that EBs are often pushed away by expanding granules, so that one polarity magnetic feature may be driven to meet other opposite polarity features.

Based on observational results,several models of EBs have been proposed,but magnetic recon-nection in the lower solar atmosphere is widely used to account for EBs(H′e noux et al.1998;Ding et al.1998;Georgoulis et al.2002;Fang et al.2003;Pariat et al.2004;Fang et al.2006a;Isobe et al.2007).Using two-dimensional quasi-steady modeling,Litvinenko(1999)demonstrated that the magnetic reconnection in the lower solar atmosphere should be most ef?cient around the region of temperature minimum.Pariat et al.(2004)proposed that EBs are a signature of resistive emergence of undulatory?ux tubes,and are produced by magnetic reconnection in bald patches or along their separatrices in the lower chromosphere.

Micro?ares,also known as sub?ares or bright points,have been observed and studied for many years(e.g.Svestka1976;Tandberg-Hanssen&Emslie1988;Fang et al.2006b).The typical size of micro?ares is from several arcseconds to about20arcseconds,with a typical lifetime of10–30min and a total energy of about1026–1029erg(e.g.Shimizu et al.2002;Fang et al.2006b).Generally speaking,micro?ares can not only appear in the solar lower atmosphere,but also in the corona, such as in EUV(Emslie&Noyes1978;Porter et al.1984)and X-ray bright points(Lin et al.1984; Krucker et al.2002;Benz&Grigis2002).Some observational results imply that the emissions in different wavelengths are coincident.For instance,by using the data of Yohkoh/SXT,SOHO/EIT and TRACE,Berghmans et al.(2001)found that the strongest EUV brightenings were counterparts of soft X-ray micro?ares.Liu et al.(2004)studied12micro?ares with BBSO/Hα,RHESSI images in 3to15keV and GOES data,and found all of them are observed in soft X-ray,hard X-ray and Hα. However,the physical relationship between them still needs to be studied further.In this paper,we are mainly interested in those micro?ares which occur in the chromosphere.To be clear,we call them chromospheric micro?ares.The most obvious characteristic in the visible spectra of chromospheric micro?ares is the weak emission at the center of the Hαline,which is not the same as for EBs. This property implies that there should be heating in the upper solar chromosphere.Semi-empirical models of chromospheric micro?ares indicate that the temperature enhancement is about1000–2200K(Fang et al.2006b).

Observations indicate that mass motions exist at or close to the locations of chromospheric micro?ares.For instance,Shimizu et al.(2002)found that chromospheric ejections were observed in some micro?ares.Non-thermal properties of some chromospheric micro?ares are explored in the microwave(e.g.Gary&Zirin1988;White et al.1995;Nindos et al.1999)and hard X-ray emissions(e.g.Nitta1997;Liu et al.2004;Qiu et al.2004).It is also found that some chromospheric micro?ares are located around or across magnetic polarity inversion lines(Porter et al.1987;Shimizu et al.2002;Liu et al.2004;Fang et al.2006b).Moreover,observational results suggest that in many cases,emerging?ux occurs about5–30min before the micro?ares appear(e.g.Tang et al.2000;

Numerical Simulation of Magnetic Reconnection 227

Shimizu et al.2002).All these observations imply that magnetic reconnection in the chromosphere could be a plausible mechanism for chromospheric micro ?ares.

Recently,Hinode observations showed the ubiquitous presence of chromospheric anemone jets outside sunspots in active regions (Shibata et al.2007).Some of them are probably related to EBs or chromospheric micro ?ares.It is believed that they are produced by magnetic reconnection in the lower solar atmosphere.

In order to study EBs and type II white-light ?ares,Chen et al.(2001)made a two-dimensional numerical MHD simulation and found that magnetic reconnection in the lower solar atmosphere can account for them in many observational aspects,such as lifetime,temperature enhancement,and mass motion.In their simulation,the effect of gravity was ignored and the initial physical parameters were uniform.To improve their results,we make numerical MHD simulations with gravity consid-ered.The in ?uence of different parameters on the results are also studied.The spectral pro ?les of EBs and chromospheric micro ?ares are calculated with the non-LTE radiative transfer theory and compared with observations.This paper is organized as follows:The numerical method is described in Section 2.The results are given in Section 3,and the discussion and conclusions are given in Section 4.

2NUMERICAL METHOD

With gravity,ionization and radiation considered,two-dimensional time-dependent compressible resistive MHD equations are taken as follows:

?ρ?t

+?·(ρv )=0,(1)ρ?υ?t

+ρ(υ·?)v +?P ?J ×B ?ρg =0,(2)?B ?t ??×(v ×B )+?×(η?×B )=0,(3)

??t P γ?1+n e χH +ρυ22 +?· P γ?1+n e χH +ρv 22

v ??·(P v )?E ·J +R ?H =0,(4)

where ?=??x ?e x +??y ?e y .The x -axis is along the horizontal direction,and the y -axis is along the vertical direction.The ?ve independent variables are the velocity (υx ,υy ),density (ρ),magnetic ?ux

function (ψ),and temperature (T ).We take ρ=1.4m H n H ,where n H is the number density of hy-drogen.The magnetic ?ux function ψis related to the magnetic ?eld (B )by B =?×(ψ?e z )+B z ?e z .E is the electric ?eld,while J =?×B /μ02is the current density,and μ0is the vacuum perme-ability.R and H stand for the radiative loss and the pre-heating terms,respectively.The gas pressure P =1.1n H κT ,κis the Boltzmann constant,and χH the ionization potential of hydrogen atoms.Also,n e is the number density of electrons,which is deduced by a modi ?ed Saha and Boltzmann formula for a pure hydrogen atmosphere (cf.Gan &Fang 1990)

n e =( φ2+4n H φ?φ)/2,

(5)and φ=1b 1 2πm e κT h 20 3/2e ?χH /κT ,b 1=2T T R

e χH 4κT (T T R ?1),where h 0is the Planck constant.We take T R =6000K (cf.Brown 1973).

228X.Y.Xu et al.

Radiative loss is important in the lower chromosphere and the upper photosphere.Generally speaking,it should be strictly solved by non-LTE radiative transfer theory.Up to now,however, it has been dif?cult to deal with in two-dimensional numerical simulations.Instead,Gan&Fang (1990)proposed an empirical formula:

R r=n H n eα(y)f(T),(6) whereα(y)and f(T)are functions of y(the height fromτ5000=1in the photosphere)and the temperature T respectively,and are de?ned as follows:

α(y)=10(2.75×10?3y?5.445)+2.3738×10?4e(?y/163),

f(T)=1.547×10?23 T

104

3/2

where the unit of y is km.The pre-heating rate is given by H=n H(n eαf)t=0.In order to perform the numerical simulation,the dimensionless form of the MHD Equations(1)–(4)is used.We take

the length scale L0=2050km,hence the Alfv′e n transit timeτA=L0/υA,whereυA is the Alfv′e n

velocity.The domain of the numerical simulation is?1≤x/L0≤1,0≤y/L0≤1.The ini-tial temperature distribution is taken from the quiet-Sun V ALC atmospheric model(Vernazza et al.

1981).Using the hydrostatic equilibrium equation,we get the initial number densities of hydrogen

atoms(n H)as shown in Figure1.

Fig.1n p distribution of the initial model.

In order to avoid too wide ranges of hydrogen density and other physical parameters in the atmosphere,we do not include the transition region,where the temperature gradient is very large. Moreover,owing to the omittance of the micro-turbulence and the exact abundance terms,the num-ber density of hydrogen atoms is one order of magnitude smaller than that of the model V ALC at the bottom boundary.Nevertheless,our computation can at least simulate the global evolution of magnetic reconnection in the lower solar atmosphere.

The initial magnetic con?guration is a force-free?eld(a current sheet)surrounded by a poten-

tial?eld,which is the same as in Chen et al.(1999).During simulations,an assumed anomalous resistivity(Cramer&Donnelly1979),

η/(μ0υA L0)=η0cos[5πx/L0]cos[10(y/L0?h)π],

is localized in a small region

|x|/L0≤0.1,|y/L0?h r|≤Δh,

Numerical Simulation of Magnetic Reconnection 229

where h r stands for the height of the reconnection point (X -point)at the y -axis,and Δh the half width of the resistivity region.In the solar atmosphere,the height of the reconnection X -point can indeed increase as the reconnection proceeds (e.g.Takeuchi &Shibata 2001;von Rekowski &Hood 2008).However,here we assume that the height of the X -point is unchanged.The reason is that in our study,we only simulate the reconnection in the lower solar atmosphere.The total height we studied is only 2050km.During the reconnection process,which we simulate,the height of the X -point does not change very remarkably.This approximation,of course,may have effects on some parameters,such as the lifetime of events.That is one of the reasons why our results are not quantitative but rather qualitative.

Owing to the symmetry about the y -axis,the calculation was performed only in the right half region.The numerical mesh consists of 161×181points,with 27points lying within the current sheet.During simulation,we overcome the divergence problem by re ?ning the simulation grid,and computing the middle value by nondimensionalization.Line-tying conditions were applied to the bottom boundary,and symmetry conditions to the left-hand side.The right-hand and the top sides were treated as open boundaries.An equivalent extrapolation was applied to all quantities at the two boundaries,except that at the top,where ρsatis ?es ?P ?y +ρg =0.With gravity,ionization and radiation considered,while heat conduction was omitted,the numerical simulations were performed with a multi-step implicit scheme (Hu 1989;Chen et al.2001;Xu et al.2005).

Fig.2Temperature distributions (color scale ),projected magnetic ?eld (solid lines )and velocity ?eld (vector arrows )at t =0τA and t =0.6τA (upper panel )and t =2τA and t =4τA (lower panel ).

230X.Y.Xu et al.

3NUMERICAL RESULTS

3.1Dynamic Process

Considering gravity,ionization and radiation,we study magnetic reconnection in the upper photo-sphere and the chromosphere with different parameters,including the intensity of the background magnetic?eld B0taken from50G to150G,which should involve as much phenomena as possible for qualitative analysis,and the anomalous resistivityη0from1×10?4to5×10?2,which is about four to?ve orders of magnitude larger than the classical resistivity(e.g.Kovitya&Cram1983).In order to study the effect of the reconnection X-point heights,we take h r=400km and1200km to represent the upper photosphere and the chromosphere respectively.Δh=300km and800km have been chosen for the two cases respectively.Figure2gives an example of the evolution of magnetic reconnection with h r=400km and B0=75G.In the?gure,colors stand for the temperature,solid lines for magnetic?eld and arrows for velocity.The top-left panel shows the initial condition,while the others correspond to the result at different times.It is noticed that for different background mag-netic?elds and X-point heights,there are different Alfv′e n time scales,which are listed in Table1.

Table1Alfv′e n Time ScalesτA

B0(G)τA(400km)(s)τA(1200km)(s)

5036058

7524039

10018029

Our results indicate that the evolution process is as follows:when the anomalous resistivity sets in,two symmetrical convergent in?ows move toward the resistivity region.At the same time,two jets are ejected vertically.Due to the lower density in the upper part of the atmosphere,the velocity of the upward jet is larger than that of the downward jet.The reconnected?eld lines below the X-point pile up due to the line-tying effect at the bottom boundary,forming the closed magnetic loop system which rises slowly.When the loop system moves close to the resistivity region,it hinders the reconnection in?ow,slowing the magnetic reconnection https://www.wendangku.net/doc/aa1968599.html,pared to the case of the uniform initial atmosphere(Chen et al.2001),the reconnection in our case can continue longer. 3.2Parameter Dependence

Figure3displays the temperature distributions when the reconnection rate R,de?ned as the closing rate of the magnetic?ux dψ/dt at the X-point(Forbes&Priest1983;Chen et al.1999),is around the maximum for different background magnetic?elds when the X-point is at the height of400km (a)and1200km(b).When magnetic reconnection takes place and the X-point is at the height of 400km,it is found that the range of temperature enhancement is from500K to1740K.When the X-point is at the height of1200km,the temperature enhancement is from930K to2320K.Our results indicate that the temperature enhancement increases with the background magnetic?eld.

Figure4shows the temperature distributions at the time of the reconnection being maximum for different values ofη0when the X-point is at the height of400km(a)and1200km(b).Figure4 demonstrates that the temperature enhancement increases withη0.This is because the Joule dissipa-tion is the main heating mechanism in our numerical simulation.

We studied the behavior of the magnetic reconnection rate,R,for the two parameters.Figure5 shows the evolution of R with different background magnetic?elds when the X-point is at the height of400km(a)and1200km(b).It is clear that the maximum of the magnetic reconnection rate is almost not related to the background magnetic?eld,but the relaxation of the rate is slower for the stronger magnetic?eld.

Numerical Simulation of Magnetic Reconnection231

Fig.3Temperature distribution resulting from different background magnetic?elds.The dashed

lines represent the initial temperature distribution in our model,which is the same as that of the

quiet-Sun atmospheric model V ALC.The background magnetic?elds are50G(dotted lines),75G

(solid lines)and100G(dash-dotted lines),respectively.The X-point heights along the y-axis,have

been taken as400km(a)and1200km(b).The value ofη0is1×10?2(a)and5×10?4(b).

Fig.4Temperature distribution resulting from different values ofη0.The X-point of magnetic

reconnections is at the height of400km(a)and1200km(b).The background magnetic?eld is

taken to be100G(a)and75G(b).The value ofη0in the panel(a)is5×10?2(dash-dotted line),

1×10?2(solid line)and5×10?3(dotted line),respectively,while that in the panel(b)is1×10?3

(dash-dotted line),5×10?4(solid line)and1×10?4(dotted line),respectively.

Figure6shows the evolution of magnetic reconnection rate with different values ofη0when the X-point is at the height of400km(a)and1200km(b).From Figure6,it can be seen that the maximum of the magnetic reconnection rate increases withη0.

In order to reproduce the temperature enhancements comparable to the semi-empirical models of EBs(Fang et al.2006a)and chromospheric micro?ares(Fang et al.2006b),we perform a survey of the parameters.The results are shown in Figures7and8.From Figure7,it can be seen that mag-netic reconnection in the upper photosphere can qualitatively explain the temperature enhancement

232X.Y.Xu et al.

Fig.5Evolution of magnetic reconnection rate,R,for different background magnetic?elds.Here

R is non-dimensional.The X-point of magnetic reconnection is located at the height of400km(a)

and1200km(b).The value ofη0is taken to be1×10?2(a)and5×10?4(b).The background

magnetic?elds are50G(dotted lines),75G(solid lines)and100G(dash-dotted lines),respectively.

Fig.6Evolution of magnetic reconnection rate,R,for different values ofη0.The X-point of mag-

netic reconnection is located at the height of400km(a)and1200km(b).The background magnetic

?eld is taken to be100G(a)and75G(b).The value ofη0in the panel(a)is taken to be5×10?2

(dash-dotted line),1×10?2(solid line)and5×10?3(dotted line),respectively,while that in the

panel(b)is1×10?3(dash-dotted line),5×10?4(solid line)and1×10?4(dotted line),respectively.

of EBs(600–1300K).Figure8implies that the temperature enhancement of chromospheric mi-cro?ares(1000–2200K)could probably be qualitatively produced by magnetic reconnection in the chromosphere.Here we emphasize that the“explanation”is“qualitative,”because it is only within our simulation framework,in which there are some assumptions and limitations(see the discussion in Sect.4).

Based on the results of our numerical simulations,we calculated the spectral excess intensity by using non-LTE radiative transfer theory.The method is similar to that given by Fang et al.(1993). Considering that the initial density distribution in our simulation is different from V ALC,which can effect the calculated spectra of Hαand Ca IIλ8542lines,we thus only compare the excess intensities

Numerical Simulation of Magnetic Reconnection

233

Fig.7Temperature distributions comparable to

the semi-empirical models of EBs(Fang et al.

2006a)with suitable parameters for magnetic re-

connection occurring in the photosphere.The X-point of magnetic reconnection is located at the height of400km.The background magnetic

?eld is taken to be100G(dash-dotted line)and

75G(solid line and dotted line).The value of η0is taken to be5×10?2(dash-dotted line and solid line)and1×10?2(dotted line

).Fig.8Temperature distributions comparable to the semi-empirical models of chromospheric mi-cro?ares(Fang et al.2006b)with suitable pa-rameters for magnetic reconnection occurring in the chromosphere.The X-point of magnetic re-connection is located at the height of1200km. The background magnetic?eld is taken to be 75G(dash-dotted line),50G(solid line)and 100G(dotted line).The value ofη0is taken to be1×10?3(dash-dotted line and solid line)and 1×10?4(dotted line).

of the Hαand Ca II lines.That is,we compute the line pro?les subtracted from the initial ones.In this case,the effect of the initial density distribution is reduced.The results are shown in Figures9 and10,which correspond to the peak time of the magnetic reconnection rate.In Figure9,the X-point is taken at the height of400km,with the background magnetic?eld being75G,andη0being 5×10?2.It can be seen that there are two emission bumps in the two wings of both Hαand Ca II λ8542lines,which are qualitatively similar to the observational results of EBs(Fang et al.2006a). In Figure10,the X-point is at the height of1200km,the background magnetic?eld is50G,and the value ofη0is1×10?3.The resulting spectra show excess emissions at the center of both Hαand Ca IIλ8542lines,which is qualitatively similar to the observational results of chromospheric micro?ares(Fang et al.2006b).

4DISCUSSION AND SUMMARY

Most of the EBs are located near the longitudinal polarity magnetic inversion lines,and many of them are accompanied by mass motions.Recent semi-empirical models of EBs indicate a tem-perature enhancement in the lower chromosphere and the upper photosphere(Fang et al.2006a). Chromospheric micro?ares have similar characteristics as EBs,but the temperature enhancement is mostly in the chromosphere,as the semi-empirical models indicated(Fang et al.2006b).All these together with some theoretical work imply that magnetic reconnection in the lower solar atmosphere can produce both EBs(e.g.H′e noux et al.1998;Ding et al.1998;Fang et al.2006a)and chromo-spheric micro?ares(e.g.Tandberg-Hanssen&Emslie1988;Liu et al.2004;Fang et al.2006b).

In our simulation,with the X-point height being400km,the size of the reconnection region be-ing300km and suitable values of the background magnetic?eld and the anomalous resistivity,the temperature enhancement by magnetic reconnection,as shown in Figure7,is similar to the observa-

234X.Y.Xu et al.

tional results of EBs(e.g.Fang et al.2006a;Kitai1983;Georgoulis et al.2002).For chromospheric micro?ares,with the X-point height being1200km and other suitable parameters,our simulation can also reproduce the temperature enhancement similar to that of observations.Moreover,the com-puted excess spectral pro?les of EBs and chromospheric micro?ares are also qualitatively similar to the observational ones,as shown in Figures9and10.It should be mentioned that our result can only represent the rise phase of chromospheric micro?ares,because our simulation was only performed below the transition region.After the upward?ow encounters the upper boundary,the simulation cannot produce reliable results.Nevertheless,our results indicate that the heating caused by mag-netic reconnection in the lower solar atmosphere can qualitatively give an explanation for the excess intensity of both EBs and chromospheric micro?ares(at least for the rise phase).

Our simulation can also reproduce some characteristics of EBs and chromospheric micro?ares, such as the lifetime and the size.Owing to the saturation in magnetic reconnection caused by the line-tying effect,the lifetime of both EBs and chromospheric micro?ares cannot be very long,as found by Chen et al.(2001).The lifetime depends mainly on the height of the X-point.According to our simulation,when the other conditions are the same,the lower the height is,the shorter the lifetime is.Chromospheric micro?ares occur in the chromosphere,being generally higher than EBs, so the lifetime of chromospheric micro?ares is naturally longer than that of EBs.Moreover,we

Fig.9Computed excess intensity of both Hαand Ca IIλ8542lines based on the X-point located at

the height of400km.The background magnetic?eld is taken to be75G,withη0being5×10?2.

Fig.10Computed excess intensity of both Hαand Ca IIλ8542lines based on the X-point located

at the height of1200km.The background magnetic?eld is taken to be50G,withη0being1×10?3.

Numerical Simulation of Magnetic Reconnection235 also found that the background magnetic?eld andη0have an effect on the lifetime.When the height of the X-point is the same,the bigger the background magnetic?eld andη0are,the shorter the lifetime is.It is worth noting that in the actual solar atmosphere,the X-point can dynamically change as the reconnection proceeds,which was demonstrated by some authors(e.g.Takeuchi and Shibata2001;von Rekowski&Hood2008).However,since in our study we only simulate the reconnection in the lower solar atmosphere,the total height we study is only about2050km.During the reconnection process,for which we perform the simulation,the height of the X-points does not change so remarkably.We thus can consider that the height of the X-points is almost unchanged. This approximation,of course,may have effects on some parameters,such as the lifetime of events. That is one of the reasons that our results are not quantitative but only qualitative.This is one of the limitations in our numerical simulation.

We would like to mention that in our simulation,we did not study the effect of ionization on the temperature enhancement,though the ionization item is included in our energy Equation(4).As illustrated by Chen et al.(2001,?g.3),when the ionization effect is included,the heating caused by magnetic reconnection in the upper chromosphere is much less than that not including the ionization effect,because in the former case most of the energy released by magnetic reconnection is converted into ionization potential.Thus,the ionization effect is important and should be considered in the numerical simulation of magnetic reconnection in the chromosphere.

It is worth indicating that our simulations have some limitations.In order to avoid too large a dynamic range of the parameters in the atmosphere,we only used a simple static equilibrium condition and limited the simulation box to be below2050km,excluding the temperature transition region,where the temperature gradient is very large.Moreover,owing to the omittance of the micro-turbulence and the exact abundance terms,the number density of hydrogen atoms is one order of magnitude smaller than that of the quiet-Sun atmospheric model,V ALC,at the bottom boundary, as seen in Figure1.Another shortcoming in our study is that we have?xed the height of the X-point,as we have stated in Section2.All these imply that our simulations cannot reproduce the real observations in details.Further improvement of this work is expected.

As a summary,we give the conclusions as follows:

(1)Our numerical simulations indicate that magnetic reconnection in the solar lower atmosphere

can qualitatively explain the temperature enhancement of EBs and chromospheric micro?ares.

(2)Our simulations can also roughly reproduce the excess Hαand Ca IIλ8542line pro?les,which

are qualitatively comparable to the observed ones.

(3)EBs and chromospheric micro?ares with different intensities can be simulated with different

parameters,including the strength of the background magnetic?eld,the anomalous resistivity, the height of the X-point,and the size of the reconnection region.Observations can be used to restrict the range of the parameters.

Acknowledgements We would like to thank Prof.P.F.Chen,who kindly provided many valuable suggestions and help.We greatly appreciate the valuable comments and suggestions from an anony-mous referee.This work was supported by the National Natural Science Foundation of China(Grant Nos.10221001,10333040,10403003,10620150099,10610099and10673004),as well as by the Major State Basic Research Development Program(973project2006CB806302).

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双引号、省略号、破折号的作用

双引号、省略号、破折号的作用省略号的作用:①表引文或引述的话有所省略；②表重复词语的省略；③表列举同类事物和序数词语的省略；④表静默或思考；⑤表说话断断续续；⑥表语言的中断；⑦表话未说完，语意未尽。破折号的作用：1.表示解释说明 2.表示语音的延长3.表示意思的转换,跳跃或转折 4.表示插说 5.电脑应用 6.加强重点7.分行举例8.用在副标题前9.标明作者10.补充说明11.表示总结上文12.表示语言的延续引号的作用：a．表示引语b．表示特定称谓c．表示特殊含义需要强调d．表示否定和讽刺引号最基本的用法是引用,引用包括直接引用和间接引用.直接引用是把人所说的话完整地记录下来；间接引用是把某人的原话非正式地、不完整地、随语意拈来放在自己的话中的引用.这类引述如果不作明白交代,就很难发现它是引用。引号除了引用外,还具有强调的作用。

省略号作用（……） 1.表示引文或引述的话里有所省略.例如： ①就在那样不平凡的时刻,在那个可纪念的地方,我第一次听见唱：二月里来,好风光,家家户户种田忙.…… ②听筒里传来十分响亮而焦灼的声音：“时间来不及了,请马上设法空运……空运!” 2.表示重复词语的省略.例如：孔乙己低声说道："跌断,跌、跌……,他的脸色,很象恳求掌柜,不要再提. 3.表示列举同类事物和序数词语的省略.例如：（场长）介绍给我们看董昆他们打的野物皮子：狐狸、貉子、獾、水獭、野猫……种类实在不少. 4.表示静默或思考.例如：何为：不行!梅伯母的身体已经经不起路上的颠簸了! 欧阳平：…… 5.表示说话断断续续.例如：他……直指着正北方向,“好,好同志……你……你把它带给……” 6.表示语言的中断.例如： ①“我并没有阔哩,我须卖了这些,再去……” ②“啊呀呀,你放了道台了,还说不阔?你现在有三房姨太太；

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小学语文五年级引号、省略号、破折号用途专项练习汇总

标点符号练习：引号的用法练习学习运用引号的练习（一） 1“说”字在前面，“说”字后面用冒号，所说的话用引号，引号里的话，一句话意思没有说完时，就用逗号，意思说完了，就用句号（问号、感叹号）。例：大树说：“来吧，孩子你会很快活的！” 练习：大树高兴地摇晃着肢体，对孩子说来吧，孩子，爬到我的树干上，在树枝上荡秋千，你会很快活的！ 2“说”字在中间时，前面的话用引号，“说”字后面用逗号，后面的话还用引号，引号里的话中标点用法同第一种情况。例：“我已经大了，不爱爬树玩了，”孩子说，“我想买些好玩儿的东西。我需要钱。你能给我一点儿钱吗？” 练习：很抱歉大树说我没有钱。我只有树叶和苹果，把它们拿去吧，孩子 3“说”字在句尾时，“说”后用句号。前面的话用引号引起来，引号里的话中标点用法同第一种情况。例：“我太老了，不能再荡秋千了。”孩子说。练习：我很疲倦，爬也爬不动了孩子说

综合练习题： 1.[“] 非常抱歉，孩子 [，][ ”]大树说 [ ，][ “] 我没有什么可以给你的了 [！][ ”] 2.[“]我没有苹果了 [！][”] [ “] 我的牙齿已经老化，吃不动苹果了[。][ ”]孩子说 [。] 3.[“] 我没有枝条了 [ ，][ ”] 大树说 [，][“ ]你没法儿在上面荡秋千了[！][ ”] [ “] 我太老了，不能再荡秋千了[ ！][ ”]孩子说 [。] 4.[“] 我现在需要的实在不多 [ ，][ ”]孩子说 [，][“]只想找个安静的地方坐坐，好好休息。我太累了[！][ ”] [“]那好吧 [，][ ”]大树说 [，]它尽量把身子挺高。 [“]你看，我这个老树墩，正好叫你坐在上面休息。来吧，孩子，坐下吧，坐在我身上休息吧 [！][ ”] 学习运用引号的练习（二）引号的作用有 : ①表示直接引用：②表示突出强调：③表示否定或者讽刺：④表示特定称谓： ⑤用来引用俗语、谚语、歇后语、古语等： 1、这样的“聪明人”还是少一点好。（） 2、这是我们组办的“热爱大自然”的手抄报。（）

省略号和破折号的作用和例句

省略号的作用和例句省略的内容主要有四：一是引文；二是重复性词语；三是类似语句；四是列举。除省略外，省略号还有以下几种用法： 1、表示沉默：例：何为：梅伯母的身体已经经不起路上的颠簸了！欧阳平：…… 2、表语言中断：例：穿长袍的问："这位是……""我的兄弟。"戴礼帽的回答。破折号也可表语言中断，但两者有不同：破折号表语言戛然而止，省略号表余音未尽。3、表语言断断续续。例：上级……派我……到这儿……工作，我没……有……完成……上级……交给我的……任务。 4、表含糊其辞，欲言又止例：我即刻胆怯了起来，便想全翻过先前的话来，"那是……实在，……我说不清……。其实，究竟有没有魂灵，我也说不清。" 5、表明语意未尽。例："可恶！然而……。"四叔说。使用省略号时应注意以下问题：（1）不可滥用省略号。一是省略号后语境不明的不能用省略号，而是没有上述特殊语意不能用省略号。（2）、用了"等"、"等等"就不能再用省略号。（省略号和"等"、"等等"有不同，省略号表示的可以是各种需要省略的，而后者只能是类似的词语或意思。）（3）要正确处理省略号前后的点号问题：一是省略号前是个完整的句子的，省略号前应使用句末标点，表示省略的是句子；二是省略号前不是完整句子的，省略号前一般不用点号，表示省略的是词语、短语；三是省略号后一般不用标点。（4）、如果省略的是一大段或几段文字，就用十二个圆点表示，单独成行，不顶格。破折号的作用和例句破折号是一个用途比较广的标号。它的主要用法可以归纳如下。 1. 用以表示对上文的解释说明或补充。例如：“亚洲大陆有世界上最高的山系——喜玛拉雅山，有目前地球上最高的山峰——珠穆朗玛峰。” 括号也表示解释说明，但是破折号引出的解释说明是正文的一部分，是较重要的信息，要读出来的。而括号里的解释说明不是正文，只是注释，没有它不影响句子的完整性，读时也不必连着正文念出来。解释说明或补充的语句如果是插在句子中间的，可以前后各用一个破折号。例如：“太阳系除了九个大行星——水星、金星、地球、火星、木星、土星、天王星、海王星和冥王星——以外，还有40个卫星以及为数众多的小行星、彗星和流星体等。”“直觉——尽管它并不总是可靠的——告诉我，这事可能出了什么问题。” 2. 表示话题的转变。例如：“我在珠海的公司干得挺顺心。老板对我不错，工资也挺高，每月三千多呢!——我能抽支烟吗？”破折号前是讲述自己情况, 后面突然转而询问对方别的事。 3. 表示话语的中断。例如：“…班长他牺——?小马话没说完就大哭起来。”“他很大了，——(顿)并且他以为他母亲早就死了的。”前一例的破折号表示下面的话没说出来。后一例表示说了半句暂时中断，停顿了一下又接着说下去。 4. 表示声音的延长。例如：“…顺——山——倒——?林子里传出我们伐木连小伙子的喊声。” 5. 表示引出下文。例如：“在一篇题为《论气节》的文章里，他对…五四?以来中国知识分子

商务英语常用缩略词词汇表大全

商务英语常用缩略词词汇表大全 a accepted 承兑 AA Auditing Administration （中国）审计署 AAA 最佳等级 abs. abstract 摘要 a/c, A/C account 帐户、帐目 a/c, A/C account current 往来帐户、活期存款帐户 A&C addenda and corrigenda 补遗和勘误 Acc. acceptance or accepted 承兑 Accrd.Int accrued interest 应计利息 Acct. account 帐户、帐目 Acct. accountant 会计师、会计员 Acct. accounting 会计、会计学 Acct.No. account number 帐户编号、帐号 Acct.Tit. account title 帐户名称、会计科目 ACN air consignment 航空托运单 a/c no. account number 帐户编号、帐号 Acpt. acceptance or accepted 承兑 A/CS Pay. accounts payable 应付帐款 A/CS Rec. accounts receivable 应收帐款 ACT advance corporation tax 预扣公司税 ACU Asia Currency Unit 亚洲货币单位 A.C.V actual cash value 实际现金价值a.d., a/d after date 开票后、出票后 ADRS asset depreciation range system 固定资产分组折旧法 BA bank acceptance 银行承兑汇票 bal. balance 余额、差额 banky. bankruptcy 破产、倒闭 Bat battery 电池 b.b. bearer bond 不记名债券 B.B., B/B bill book 出纳簿 B/B bill bought 买入票据、买入汇票 b&b bed & breakfast 住宿费和早餐费 b.c. blind copy 密送的副本 BC buyer credit 买方信贷 B/C bills for collection 托收汇票 B.C. bank clearing 银行清算 b/d brought down 转下页 Bd. bond 债券 B/D bills discounted 已贴现票据 B/D bank draft 银行汇票 b.d.i. both dates inclusive, both days inclusive 包括头尾两天 B/E bill of entry 报关单 b.e., B/E bill of exchange 汇票

重复翻译法

You were born to run. And we were born to help you do it better. 奔跑是你的天性，让你跑得更快是我们的天职。运用了多种修辞手法：重复、押头韵 Skin firming/toning agent 紧肤水/爽肤水成分 Coriander 芫荽、香菜Lavender 薰衣草 Adidas Sports Shoes Over twenty-eight years ago, adidas gave birth to a new idea in sports shoes. And the people who wear our shoes have been running and winning ever since. In fact, adidas has helped them set over 400 world records in track and field alone. Maybe that’s why more and more football, soccer, basketball, baseball and tennis players are turning to adidas. They know that, whatever their game, they can rely on adidas workmanship and quality in every product we make. So whether you are pounding the roads on a marathon, or just jogging around the block, adidas shall be on your feet. You were born to run. And we were born to help you do it better. You’ll find us anywhere smart sports people buy their shoes. Adidas, the all sports people. 阿迪达斯运动鞋 28年前，阿迪达斯为运动鞋注入了一种全新的理念，从此以后，脚穿阿迪的运动健儿风驰电掣、频频夺冠。事实上，仅在田径场上阿迪达斯就帮助人们创造了400多项世界记录。或许正因为如此，才有越来越多的足球、橄榄球、篮球、棒球和网球运动员青睐这个品牌。他们知道，无论从事哪项运动，他们都可以信赖阿迪达斯

破折号、省略号的作用

破折号得作用 “——”,破折号就是小学课文中常见得标点符号,它一般有以下几种用法: 1、表示破折号后面就是解释说明得部分。 (1)各国政府——无论专制政府或共与政府都驱逐她。 (2)带工老板或者打杂得拿着一叠叠得名册,懒散地站在正门口——好像火车站剪票处一般得木栅子前面2、表示意思得递进。每年——特别就是水灾、旱灾得时候,这些在日本厂里有门路得带工…… 3、表示意思得转换、跳跃或转折。 (1)“今天好热啊！——您什么时候去上海？” (2)我本来不想去,可就是俺婆婆非叫我再去瞧瞧她——有什么瞧头啊！ 4、表示语音得延长 (1)“小林——,我来了！”她大喊着 (2)“呜——呜——呜”小男孩大声哭起来。 (3)我们在天安门前深情得呼唤:周——总——理——5、表示语音较大得停顿或中断。那个时候在无锡得人,我倒问过,可就是——(表示说话中断) 人教版六年级上册破折号汇总

1、先就是听见它得声音从,从很远得山林里传来,从很高得山坡山传来——沙啦啦,沙啦啦……( 1、表示破折号后面就是解释说明得部分。) 2、来得突然——跟着一阵阵湿润得山风,跟着一缕缕轻盈得云雾,鱼,悄悄地来了。( 1、表示破折号后面就是解释说明得部分。) 3、丁——冬——丁——冬……( 4、表示语音得延长) 4、它们散居在两棵大树下面——这就是两簇野灌丛……(1、表示破折号后面就是解释说明得部分。) 5、这样得“路”,还可以过汽车——汽车吼叫着,车身摇晃着,卵石挤碰着…… (1、表示破折号后面就是解释说明得部分。) 6、孩子虽然不多——只有两个,可就是全靠她一个人张罗。( 1、表示破折号后面就是解释说明得部分。) 7、我瞧见一堆焦黄得马草——这些日子我卖给她所有得马草。( 1、表示破折号后面就是解释说明得部分。) 8、她就是一位老太太,非常瘦,满头白发,不过——她就是聋子。( 4、表示语音得延长) 9、巴拉那河上有一条世界著名得大瀑布——赛特凯达

附录笔记常用符号和缩略语(建议打印)

附录一笔记常用符号和缩略语(Note-taking: Useful Signs and Abbreviations) 1．常用笔记符号：符号信息意义箭头符号 ↑ 上升；提高；增强；上涨；增长；扩大；起飞；升空；提拔；晋升（grow, expand, develop, rise, go up, increase , ascend, launch, skyrocket, soar, appreciation, promote, upwards） ↓ 下降；下沉；降低；滑坡；轰炸；减少；恶化；降职；削减/裁减（drop to, bomb, jump, go down, descend, decrease, deteriorate, depreciation, reduce, downwards） ↗上扬；渐渐好转（become better and better） ↘下挫；不断亏损（become worse and worse） → 出口；去；向前；出国；前往；运往；导致；发展成为… （export to, enter, arrive in/at, present to, result in, send to, transmit to, lead to, export to, cause） ← 回顾；从前；进口；倒退；来自；源于（come from, originate from, receive from, go back to, import from）例如：café ← French意为: café源自于法语数学符号 + 增加；补充；除此之外；另外(furthermore, in addition to, with, and, besides, etc) —减少；删除；缺乏（minus, lack, deduct, except, subtract） ×表示“不对的，错的，坏的，不好的，臭名昭著的”（mistake, incorrect, wrong, bad, inappropriate, notorious） > 超过，大于，胜过，优于（more than, bigger than, surpass, better than, superior to）＞＞大大超过(much greater than, much more than) < 小于，不足，次于，逊色（fewer than, less than, worse than, inferior to）＜＜远远少于(much less than) = 等于符号（equal) 在听力笔记中相当于“与…一样”（equal to, the same as)，另外可以表示“是… 的对手“（a rival, a competitor)等意思。还可以表示“同等”概念(means, that is to say, in other words, the same as, etc) ≠ 表示否定意思“不等于”（not equal to )，“不同”（be different from），或者“无敌、不是…对手” （matchless, peerless, no match for） ≈ 表示“大约，左右”（approximately, around, about, or so） ∑ 总和；总数（total, the total number/sum, totally） ∵表示“原因，理由”（because, owing to, thanks to, due to） ∴表示“结果、结论”（therefore, as a result, consequently, so）标点符号：表示“说，告诉，认为，宣称，声明，抗议，譬如”（say, speak, tell, declare, announce, protest, such as） ? 表示“问题，疑问，问”（problem, issue, question, doubt, suspicious, skeptical, ask, puzzle, confused, mystery, bewildered） ·（1）表示“观点，意见，注意，论点”（viewpoint, opinion, idea, point）（2）表示不同的时间概念。如用“d”表示“今天”（today)，那么“昨天”（yesterday)即用“·d”表示，“前天”（the day before yesterday)同理类推，可记为“··d”，3天前（Three days ago)可写成“·3d”； “d·”表示“明天”（tomorrow)，“d··”表示“后天”（the day after tomorrow)。

破折号和省略号用法练习

一、破折号主要用法 1.表示解释说明例如：“亚洲大陆有世界上最高的山系——喜马拉雅山，有目前地球上最高的山峰——珠穆朗玛峰。” 解释说明或补充的语句如果是插在句子中间的，可以前后各用一个破折号。例如：（1）“太阳系除了九个大行星——水星、金星、地球、火星、木星、土星、天王星、海王星——以外，还有40个卫星以及为数众多的小行星、彗星和流星体等。” （2）“直觉——尽管它并不总是可靠的——告诉我，这事可能出了什么问题。” 2.表示话题转换例如：“我在珠海的公司干得挺顺心，工资也挺高，每月三千多呢!——我能抽支烟吗？”3．表示插说例如（1）“这种分配法可以算——在我的经验中——天下第一了”（选自老舍《想北平》）（2）“就拿他做个例子吧，——其实，这事每人都会碰到——有一次他……” 4.表示语言中断例如：“‘班长他牺——’小马话没说完就大哭起来。” 5.表示声音延长例如：“‘顺——山——倒——’林子里传出伐木连小伙子的喊声。” 6.表示意思的递进。例如：自然是读着，读着，强记着——而且要背出来。二、破折号用法练习 1.选出下列句中破折号用法与例句相同的一项。（）例句：就从这我才明白，在一个比黄连还苦的青蛋蛋里藏着的，才是核桃——我想念的朋友。 A.“今天好热啊！——你什么时候去上海？” B.“将军家的厨师来了，问他好了——喂，普洛诃尔！过来吧……” C“哟，祥子？怎——”她刚要往下问，一看祥子垂头丧气的样子，车上拉着铺盖卷，把话咽了回去。 D.三只五只的白鸥轻轻地掠过，翅膀扑着波浪，——一点一点躁怒起来的波浪。 2.选出下列句中破折号用法与例句相同的一项。（）例句：陈二奶奶带着“童儿”——四十来岁的一位黄脸大汉----快到掌灯的时候才来到。A．她说得非常大方，自然。那件粉红色的卫生衣忽然——在祥子眼中——仿佛肃静了许多。B．一进屋门，两个儿子——一个十三，一个十一岁——就想往外躲。 C．我们曾经把解决人民内部矛盾的方法具体化为一个公式，叫做“团结——批评——团结”。D．于是她使劲地张了张嘴：“浩——波——” 3.在下列句子中，与例句破折号作用相同的一项是（）例句：精简机构以后，南京宏远制衣有限公司改变了“四多一少”——临时机构多、管理人员多、服务人员多、辅助人员多、第一线生产人员少——的状况。 A．“股市行情发生了很大变化——请把湿毛巾递给我——马上开会修改方案。”罗经理气喘吁吁地对我说。 B．“直觉——尽管它并不总是可靠的——告诉我，这事可能出了什么问题。” C．“这种分配法可以算——在我的经验中——天下第一了” D．在这个时候，专卖手脚的哥儿们的手与脚就一律贵起来：“前门，东车站！”“哪儿？”“东----车----站！”“呕，干脆就给一块四毛钱！不用驳回，兵荒马乱的！” 4.在下列句子中，与例句破折号作用相同的一项是例句：祥子把钱——一打儿钞票----接过来，愣了一会儿，找不到话说。 A．我国的四大发明——火药、印刷、指南针、造纸术——对世界历史的发展有伟大的贡献。

引号、破折号、省略号的作用练习(改)

二联小学五年级第二学期语文基础卷一班级_________ 姓名__________ 成绩__________ 引号的作用： 1、表示引用 2、表示特殊含义 3、表示否定或讽刺（一）请把引号的作用相对应的序号填在括号内 1、石碑上，“革命烈士永垂不朽”这八个大字在阳光下闪闪发光。（） 2、贺捷生奶奶居然可以“走”完长征，十分了不起。（） 3、春天，布谷鸟“布谷、布谷”地啼叫着。（） 4、机器人被人们誉为“千里眼”、“顺风耳”、“飞毛腿”。（） 5、我问布谷鸟：“你做些什么”（） 6、听爷爷说，鸟儿是会“说话”的。（） 7、不过，这张“网”是通过无数条“线”把亿万台电脑连接起来的。（） 8、我们可以足不出户逛“网上商场”，用“电子钱包”付款。（） 9、我们现在生活的世界真像一个“地球村”。（） 10、富兰克林大胆地提出，那是大自然的一种“放电现象”。（） 11、富兰克林还发明了“避雷针”。（） 12、这里关在“笼子”里的不是动物，而是游人！（） 13、“斑马！斑马！”阿里指着右前方喊起来。（） 14、人们把狮子称为“百兽之王”。（）破折号的作用： 1表示对上文的解释或补充说明。2表示话题的转换。 3表示意思的递进。4表示声音延长。二、请把破折号的作用的相应序号写在括号内 1、我把带着体温的银元放到他手里——他的手多瘦啊！（） 2、先是听见它的声音从，从很远的山林里传来，从很高的山坡山传来——沙啦啦，沙啦啦。

（） 3、孩子虽然不多——只有两个，可是全靠她一个人张罗。（） 4、她是一位老太太，非常瘦，满头白发，不过——她是聋子。（） 5、巴拉那河上有一条世界著名的大瀑布——赛特凯达斯大瀑布。（） 6、小狐狸也许在叫“妈妈——妈妈——”，这小狐狸真可怜（） 7、一个矮小而结实的日本中年人——内山老板走了过来。（） 8、我摸了摸里衫上的衣袋——袋里只剩下一块多钱……（） 9、“嗨——”李莱发出震耳欲聋的喊声。（） 10、他飞奔回客店，把刚才弹的曲子——《月光曲》记录了下来（） 11、他不喜欢乘马车游公园—除非为了炫一下他的新衣服。（）省略号的作用： 1表示说话的断断续续。2表示内容的省略。 3表示列举的省略。4表示意犹未尽。三、请把省略号的作用相对应的序号写在括号内 1、家乡小桥的名称也美极了。千岁桥、如意桥、震龙桥、元宝桥、娘娘桥、骆驼桥……（） 2、她轻轻地哼起了《摇篮曲》：“月儿明，风儿静，树叶儿遮窗棂……” （） 3、我支支吾吾地说“我没……没看……看见。”（） 4、“我嘛……缝缝补补……风吼得这么凶，真叫人害怕。我可替你担心呢！”桑那说。（） 5、我鼻子一酸，攥着钱跑了出去……（） 6、在新垦的田野上，荷兰人种满自己心爱的花儿，郁金香、风信子、百合花……

标点符号复习(引号的用法复习、省略号的作用、破折号的作用)

五年级语文标点符号的作用练习姓名学号一、引号 1、引号的作用： ①表示直接引用：②表示突出强调：③表示否定或者讽刺：④表示特定称谓： ⑤用来引用俗语、谚语、歇后语、古语等： 2、练习 1、这样的“聪明人”还是少一点好。（） 2、这是我们组办的“热爱大自然”的手抄报。（） 3、“满招损，谦受益”这句格言，流传到今天至少有两千年了。（） 4、罪恶的子弹还要挟着“和平之花”。（） 5、像这样一条多灾多难的祸河，怎么能成为中华民族的“摇篮”呢？（） 6、说他“特别”，因为他爱鱼到了忘我的境界。（） 7、鲸鱼的外形是极为理想的“流线型”。（） 8、大家采集起“茅茅针”来。（） 9、爸爸一定送你一顶“蓝盔”。（） 10、从山脚向上望，只见火把排成许多“之”字形，一直连到天上。（） 11、罪恶的子弹还要挟着“和平之花”。（） 12、像这样一条多灾多难的祸河，怎么能成为中华民族的“摇篮”呢？（） 13、他在学下读书的时候，大家都称他为“辩论家”。（） 14、说他“特别”，因为他爱鱼到了忘我的境界。（） 15、大家采集起“茅茅针”来。（） 16、荷兰获得了“欧洲花园”的美誉。（）二、省略号 1、作用 ①表引文或引述的话有所省略；②表重复词语的省略； ③表列举同类事物和序数词语的省略；④表静默或思考； ⑤表说话断断续续；⑥表语言的中断； ⑦表话未说完，语意未尽。

2、练习（1）“我再也受不住了！……我给您跪下了，我会永远为您祷告上帝。带我离开这儿吧，要不，我就要死了！……”（）（2）短短的一段新闻还没看完，就听见啪，啪……几声尖锐的枪响，接着就是一阵纷乱的喊叫。（）（3）我的生活没有指望了，连狗都不如……我问候安辽娜，问候独眼的艾果尔，问候马车夫。（）（4）我常常会想起这位顶碗少年，想起他那一次的演出，每每想起，总会有一阵微微的激动……（）（5）观众们屏住气，目不转睛地盯着他头上的碗……眼看身体已经转过来。（）（6）听到这个消息，我们仿佛又看见老人和海鸥在翠湖边相依相随......(语意未尽) （7）”你看他们那小模样！啧啧......”海鸥听见老人呼唤，马上飞了过来，把团团围住。( ) （8）她轻轻地哼起了《摇篮曲》：“月儿明，风儿静，树叶儿遮窗棂啊……”() （9）辞典可以告诉我们许多词语，包括人名、地名、制度、成语、典故……的含义。( ) （10）“我……对不起……大家，我……没有……完成……任务。”() （11）“生活？生活当然……”猩猩犹豫着，“不过，乐在其中，那个'乐'字总有点刺眼。”（）三、破折号 1、作用（1）用以表示对上文的解释说明或补充。

商务英语常用省略语表

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