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A Tactile Micro Gripper with Piezoelectric Actuator based on microsystem technology

A Tactile Micro Gripper with Piezoelectric Actuator based on microsystem technology
A Tactile Micro Gripper with Piezoelectric Actuator based on microsystem technology

A Tactile Micro Gripper with Piezoelectric Actuator

Based on Microsystem Technology

Feng Qiao, Helmut Wurmus

Ilmenau Technical University, Department of Microsystem Technology;

P.O.Box 100565, D-98684 Ilmenau, GERMANY. Tel: 0049-3677-691295, Fax: -691296 Email: Feng.Qiao@mb.tu-ilmenau.de

Abstract

For handling and assembling of small components one sort of micro gripper was developed. It has planar structure and flexure hinges, uses piezoelectric actuation and is fabricated with standard microsystem technology. Micro grippers made of both silicon and glass have been fabricated. Due to its etching angle, gripper made of silicon has no ideal hinge form, which leads to no good mechanical feature, while at glass almost all designs can be fabricated. HF signal was imposed at piezoactutor. A combination of resonant vibration of gripper structure and utilizing self-sensing effect of piezoelectric materials enables micro gripper tactile.

Key words: micro gripper flexible hinge piezoelectric actuator tactile

Introduction

As a rapidly rising field, more and more micro components in different branches have been produced. Thus handling these micro components become necessary. Since the development of parallel-plate electrostatic micro gripper in the University of California [1], some micromachined grippers have been proposed in the literature. They use different actuation types: electrostatic, piezoelectric, suction, SMA and thermal bimorph effect [2,3]. Among them micro gripper with sensitivity of ETH Zürich [4] attracts attention.

In Ilmenau Technical University micro grippers with planar structure made of silicon or photosensitive glass have been developed. It also uses planar piezoactuator (PZT), which simplifies the assembling work. In this paper one novel idea of combine resonant vibration of gripper structure and self-sensing effect of piezoelectric materials to enable gripper sensitive is presented.

Design and Fabrication

For the fabrication with microsystem technology, a planar structure gains advantage. This type of micro gripper uses piezoelectric actuation. Due to the limited produced displacement of piezoelectric actuator, a four-bar linkage mechanism is used to amplify the displacement ( Figure 1 ). Using compliant mechanism without screws brings much convenience. In this situation flexible hinges ( Figure 2 ) are used, which are also easy to fabricate using lithography and etching technology. The construction for flexure hinges and calculation of those dynamics will not be discussed in details here.

Figure 1: Mechanism and sketch of micro gripper

The compliance of this type of flexure hinge is ( see Fig. 2 ) :

2

/52

/129t

b R M Z Z ?????=πα (1)where ε is the Young’s modulus. And the stiffness of flexure hinge is the reciprocal of the compliance.For the fabrication both silicon and glass have been used as standard materials for microsystem technology. The fabrication will be done with standard process: with photo-lithographi

c metho

d to get its outline, then th

e wafer will be etched.

Due to its etching angle in fabrication, the hinge form of silicon-gripper can not be optimised as at glass wafer in Figure 2(Figure 3), which affects its mechanical features. Glass, in normal state, has an amorphous structure. It will be etched in all directions as an isotropic material. The UV-exposure changes the inner structure of a photosensitive glass. Through a final thermal treatment a real crystallisation will be generated. After these two processes a so-called anisotropic property will be got and glass can be etched as a real anisotropic material. The fabricating steps are listed in Fig.4. Compared with silicon,photosensitive glass has the advantage of being transparent, high

aspect ratio and can generate any outline, which is impossible at silicon because of its etching angle. Thus grippers made of glass were chosen for further usage.

characteristics of one microgripper with dimensions of 8.7mm ×13mm ×0.5mm

Without extending the gripper finger length, with simply changing construction parameter for flexure hinges different tip-displacement demands can be fulfilled . At another type with the same dimensions as the one shown in Fig.5, tip displacement with ±2×120μm at ±200V has been realised, and the maximal gripping force amounts 2mN. According to the theoretical calculation, the gripping force ought to be much higher. Perhaps the flexure hinges have consumed too much mechanical energy.

Novel Idea Enabling Micro Gripper Sensitive

In technology it’s difficult to bring a sensing layer down to the glass service. A novel method to bring it sensitivity will be used.

As shown in Figure 6, piezoelectric ceramic is covered with metallic layers on both sides, which serve as contact pad. At one side the metallic layer is cut into two parts. One

part is used for actuating signal, the other for sensing signal. The sensor-part uses the inverse piezoelectric effect. At actuator-part DC-voltage overlapped with AC-signal is imposed. DC-voltage drives the gripper arm and AC-signal with small amplitude is used for sensing. Normally the sensing signal is also unclear opposite noise. Direct measuring brings no satisfying result. Thus HF-vibration helps to find one solution.For one free mechanical structure, for example a micro gripper without object, there are several resonant frequencies due to its elasticity. And at one micro gripper three resonant frequencies are found: 737 Hz,1605 Hz and 2340 Hz. And at resonant frequencies the phase shift between sensing and actuating signals is about π/2 (Figure 7). At resonant frequency the gripping process will be obvious. After gripping object both amplitude and phase of sensing signal will be greatly changed, which can be used as a criterion for detecting object.

(a) (b)

Figure 7 Dynamic features of free gripper: (a)Sensor signal spectrum; (b) Amplitude of sensing signal and phase shift between sensing and actuating signals around one resonant frequency (1605Hz): DC = 0V, AC-signal-amplitude = 8V

At one resonant frequency (1605Hz), the sensing signals of free gripper and gripper with object are shown in Figure 8. In Figure 8 (a), a little vague figure of gripper can be seen, because the free gripper vibrates at resonance. In Figure 8 (b), about π/2 phase shift between sensing and actuating signal can be observed. Correspondingly, the pictures in (c) (d) present

sensing signals after gripping object, and the sensing signal

amplitude decreases greatly where the resonance disappeared.To investigate the gripping process, at beginning point one frequency at not exact resonance was chosen. Naturally when the DC-voltage is imposed on piezoactuator, the resonant frequencies will also depart from the originals because of the generated mechanical stress at flexure hinges. For gripping test one frequency of 750 Hz was chosen, while the original was 737Hz. And the AC-signal amplitude (p-p) was reduced to 4v. In

running course of gripping with object in Fig. 9, at point P1

gripper tip just touched object, the resonant vibration was obstructed, which led to a sudden jump of phase shift up to 180degree. The gripper tips moved further towards inside till P2. At

P2 the sensing signal disappeared and there was only noise signal till P3. From P3 there appeared sensing signal again, with constant phase shift. We can conclude that under this situation there existed one firm gripping and the vibration of gripper tip was transferred through object. Also in running course of phase

shift in Fig. 9, the similar conclusion can be got from points A1, A2 and A3.

Figure 8 (a) Figure 8 (c)

Figure 8 (b) Figure 8 (d)

Figure 8: (a) resonance of gripper tip; (b) actuating signal(above) and sensing signal under resonance;

(c) one lens-carrier in gripper; (d) actuating signal (above) and sensing signal after gripping lens-carrier. Meaningfully the points P1, P2 and P3 coincide well with the points A1, A2 and A3, which means from both sensing amplitude and phase shift running courses information for gripping process can be got.

Discussion and Further Development

The gripping tests were executed on different grippers. The resonant frequencies differ from each other a little. But with this method the gripping information could always be got. For further optimisation electronic circuits for automatically searching resonant frequencies within certain frequency field will be developed. We hope more information could be got through HF-vibrating.

References:

[1] Patrick B. Chu; Kristofer S.J. Pister: Analysis of Close-loop Control of Parallel-Plate Electrostatic MicroGrippers; IEEE Intl. Conf. On Robotics and Automation, San Diego, CA 1994

[2] E. Westk?mpfer, R.D. Schraft, C. Bark, etc.: Adhesive Gripper – a new approach to handling MEMS; ACTUATOR 96, 5th International Conference on New Actuators, Bremen

[3] P. Lerch, C. K. Slimane, B. Romanowicz and P. Renaud: Modelization and characterization of asymmetrical thermal micro-actuators; J. Micromech. Microeng. 6 (1996), 134 – 137

[4] G. Greitmann, R. A. Buser: A tactile microgripper for application in Microrobotics; SPIE Photonics East: Int. Symp. on Intelligent Systems and Advanced Manufacturing; Boston, Massachussettes, Nov. 1996

[5] R. Kerschkerjan, F. Qiao, H. Wurmus : Piezoelectric X-Y-Micropositioner made of photosensitive glass to form one micro-handling unit. Actuator 2000, Bremen, June 2000

初中英语代词用法全解及练习含答案

1、人称代词顺口溜:人称代词有两类,一类主格一类宾;主格代词本领大,一切动作由它发;宾格代词不动脑,介动之后跟着跑。 2、物主代词顺口溜:物主代词不示弱,带着‘白勺’来捣乱;形容词性物主代,抓住名词不放松; 1、人称代词的主格在句子中作主语或主语补语。一般在句首,动词前。 例如:John waited a while but eventually he went home. 约翰等了一会儿,最后他回家了。 John hoped the passenger would be Mary and indeed it was she. 约翰希望那位乘客是玛丽,还真是她。 说明:在复合句中,如果主句和从句主语相同,代词主语要用在从句中,名词主语用在主句中。在电话用语中常用主格。 例如:When he arrived, John went straight to the bank. 约翰一到就直接去银行了。 I wish to speak to Mary. This is she. 我想和玛丽通话,我就是玛丽。 2、人称代词的宾格在句中作宾语或表语,在动词或介词后。 例如:Do you know him?(作宾语) 你认识他吗? Who is knocking at the door?It’s me. (作表语) 是谁在敲门?是我。 说明:单独使用的人称代词通常用宾格,即使它代表主语时也是如此。 例如:I like English. Me too. 我喜欢英语。我也喜欢。 3、注意:在动词be 或to be 后的人称代词视其前面的名词或代词而定。 例如:I thought it was she.我以为是她。(主格----主格) I thought it to be her.(宾格----宾格) I was taken to be she.我被当成了她。(主格----主格) They took me to be her.他们把我当成了她。(宾格----宾格) 4、人称代词并列时的排列顺序 1)单数人称代词并列作主语时,其顺序为: 第二人称→第三人称→第一人称 即you and I he/she/it and I you, he/she/it and I 顺口溜:第一人称最谦虚,但若错误责任担,第一人称学当先。 例如:It was I and John that made her angry. 2)复数人称代词作主语时,其顺序为: 第一人称→第二人称→第三人称 即we and you you and they we, you and they

With的用法全解

With的用法全解 with结构是许多英语复合结构中最常用的一种。学好它对学好复合宾语结构、不定式复合结构、动名词复合结构和独立主格结构均能起很重要的作用。本文就此的构成、特点及用法等作一较全面阐述,以帮助同学们掌握这一重要的语法知识。 一、 with结构的构成 它是由介词with或without+复合结构构成,复合结构作介词with或without的复合宾语,复合宾语中第一部分宾语由名词或代词充当,第二部分补足语由形容词、副词、介词短语、动词不定式或分词充当,分词可以是现在分词,也可以是过去分词。With结构构成方式如下: 1. with或without-名词/代词+形容词; 2. with或without-名词/代词+副词; 3. with或without-名词/代词+介词短语; 4. with或without-名词/代词 +动词不定式; 5. with或without-名词/代词 +分词。 下面分别举例: 1、 She came into the room,with her nose red because of cold.(with+名词+形容词,作伴随状语)

2、 With the meal over , we all went home.(with+名词+副词,作时间状语) 3、The master was walking up and down with the ruler under his arm。(with+名词+介词短语,作伴随状语。) The teacher entered the classroom with a book in his hand. 4、He lay in the dark empty house,with not a man ,woman or child to say he was kind to me.(with+名词+不定式,作伴随状语)He could not finish it without me to help him.(without+代词 +不定式,作条件状语) 5、She fell asleep with the light burning.(with+名词+现在分词,作伴随状语) Without anything left in the with结构是许多英 语复合结构中最常用的一种。学好它对学好复合宾语结构、不定式复合结构、动名词复合结构和独立主格结构均能起很重要的作用。本文就此的构成、特点及用法等作一较全面阐述,以帮助同学们掌握这一重要的语法知识。 二、with结构的用法 with是介词,其意义颇多,一时难掌握。为帮助大家理清头绪,以教材中的句子为例,进行分类,并配以简单的解释。在句子中with结构多数充当状语,表示行为方式,伴随情况、时间、原因或条件(详见上述例句)。 1.带着,牵着…… (表动作特征)。如: Run with the kite like this.

精神分裂症的病因及发病机理

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with的用法大全

with的用法大全----四级专项训练with结构是许多英语复合结构中最常用的一种。学好它对学好复合宾语结构、不定式复合结构、动名词复合结构和独立主格结构均能起很重要的作用。本文就此的构成、特点及用法等作一较全面阐述,以帮助同学们掌握这一重要的语法知识。 一、 with结构的构成 它是由介词with或without+复合结构构成,复合结构作介词with或without的复合宾语,复合宾语中第一部分宾语由名词或代词充当,第二部分补足语由形容词、副词、介词短语、动词不定式或分词充当,分词可以是现在分词,也可以是过去分词。With结构构成方式如下: 1. with或without-名词/代词+形容词; 2. with或without-名词/代词+副词; 3. with或without-名词/代词+介词短语; 4. with或without-名词/代词+动词不定式; 5. with或without-名词/代词+分词。 下面分别举例:

1、 She came into the room,with her nose red because of cold.(with+名词+形容词,作伴随状语) 2、 With the meal over , we all went home.(with+名词+副词,作时间状语) 3、The master was walking up and down with the ruler under his arm。(with+名词+介词短语,作伴随状语。) The teacher entered the classroom with a book in his hand. 4、He lay in the dark empty house,with not a man ,woman or child to say he was kind to me.(with+名词+不定式,作伴随状语) He could not finish it without me to help him.(without+代词 +不定式,作条件状语) 5、She fell asleep with the light burning.(with+名词+现在分词,作伴随状语) 6、Without anything left in the cupboard, she went out to get something to eat.(without+代词+过去分词,作为原因状语) 二、with结构的用法 在句子中with结构多数充当状语,表示行为方式,伴随情况、时间、原因或条件(详见上述例句)。

with用法归纳

with用法归纳 (1)“用……”表示使用工具,手段等。例如: ①We can walk with our legs and feet. 我们用腿脚行走。 ②He writes with a pencil. 他用铅笔写。 (2)“和……在一起”,表示伴随。例如: ①Can you go to a movie with me? 你能和我一起去看电影'>电影吗? ②He often goes to the library with Jenny. 他常和詹妮一起去图书馆。 (3)“与……”。例如: I’d like to have a talk with you. 我很想和你说句话。 (4)“关于,对于”,表示一种关系或适应范围。例如: What’s wrong with your watch? 你的手表怎么了? (5)“带有,具有”。例如: ①He’s a tall kid with short hair. 他是个长着一头短发的高个子小孩。 ②They have no money with them. 他们没带钱。 (6)“在……方面”。例如: Kate helps me with my English. 凯特帮我学英语。 (7)“随着,与……同时”。例如: With these words, he left the room. 说完这些话,他离开了房间。 [解题过程] with结构也称为with复合结构。是由with+复合宾语组成。常在句中做状语,表示谓语动作发生的伴随情况、时间、原因、方式等。其构成有下列几种情形: 1.with+名词(或代词)+现在分词 此时,现在分词和前面的名词或代词是逻辑上的主谓关系。 例如:1)With prices going up so fast, we can't afford luxuries. 由于物价上涨很快,我们买不起高档商品。(原因状语) 2)With the crowds cheering, they drove to the palace. 在人群的欢呼声中,他们驱车来到皇宫。(伴随情况) 2.with+名词(或代词)+过去分词 此时,过去分词和前面的名词或代词是逻辑上的动宾关系。

独立主格with用法小全

独立主格篇 独立主格,首先它是一个“格”,而不是一个“句子”。在英语中任何一个句子都要有主谓结构,而在这个结构中,没有真正的主语和谓语动词,但又在逻辑上构成主谓或主表关系。独立主格结构主要用于描绘性文字中,其作用相当于一个状语从句,常用来表示时间、原因、条件、行为方式或伴随情况等。除名词/代词+名词、形容词、副词、非谓语动词及介词短语外,另有with或without短语可做独立主格,其中with可省略而without不可以。*注:独立主格结构一般放在句首,表示原因时还可放在句末;表伴随状况或补充说明时,相当于一个并列句,通常放于句末。 一、独立主格结构: 1. 名词/代词+形容词 He sat in the front row, his mouth half open. Close to the bank I saw deep pools, the water blue like the sky. 靠近岸时,我看见几汪深池塘,池水碧似蓝天。 2. 名词/代词+现在分词 Winter coming, it gets colder and colder. The rain having stopped, he went out for a walk.

The question having been settled, we wound up the meeting. 也可以The question settled, we wound up the meeting. 但含义稍有差异。前者强调了动作的先后。 We redoubled our efforts, each man working like two. 我们加倍努力,一个人干两个人的活。 3. 名词/代词+过去分词 The job finished, we went home. More time given, we should have done the job much better. *当表人体部位的词做逻辑主语时,不及物动词用现在分词,及物动词用过去分词。 He lay there, his teeth set, his hands clenched, his eyes looking straight up. 他躺在那儿,牙关紧闭,双拳紧握,两眼直视上方。 4. 名词/代词+不定式 We shall assemble at ten forty-five, the procession to start moving at precisely eleven. We divided the work, he to clean the windows and I to sweep the floor.

精神分裂症的发病原因是什么

精神分裂症的发病原因是什么 精神分裂症是一种精神病,对于我们的影响是很大的,如果不幸患上就要及时做好治疗,不然后果会很严重,无法进行正常的工作和生活,是一件很尴尬的事情。因此为了避免患上这样的疾病,我们就要做好预防,今天我们就请广州协佳的专家张可斌来介绍一下精神分裂症的发病原因。 精神分裂症是严重影响人们身体健康的一种疾病,这种疾病会让我们整体看起来不正常,会出现胡言乱语的情况,甚至还会出现幻想幻听,可见精神分裂症这种病的危害程度。 (1)精神刺激:人的心理与社会因素密切相关,个人与社会环境不相适应,就产生了精神刺激,精神刺激导致大脑功能紊乱,出现精神障碍。不管是令人愉快的良性刺激,还是使人痛苦的恶性刺激,超过一定的限度都会对人的心理造成影响。 (2)遗传因素:精神病中如精神分裂症、情感性精神障碍,家族中精神病的患病率明显高于一般普通人群,而且血缘关系愈近,发病机会愈高。此外,精神发育迟滞、癫痫性精神障碍的遗传性在发病因素中也占相当的比重。这也是精神病的病因之一。 (3)自身:在同样的环境中,承受同样的精神刺激,那些心理素质差、对精神刺激耐受力低的人易发病。通常情况下,性格内向、心胸狭窄、过分自尊的人,不与人交往、孤僻懒散的人受挫折后容易出现精神异常。 (4)躯体因素:感染、中毒、颅脑外伤、肿瘤、内分泌、代谢及营养障碍等均可导致精神障碍,。但应注意,精神障碍伴有的躯体因素,并不完全与精神症状直接相关,有些是由躯体因素直接引起的,有些则是以躯体因素只作为一种诱因而存在。 孕期感染。如果在怀孕期间,孕妇感染了某种病毒,病毒也传染给了胎儿的话,那么,胎儿出生长大后患上精神分裂症的可能性是极其的大。所以怀孕中的女性朋友要注意卫生,尽量不要接触病毒源。 上述就是关于精神分裂症的发病原因,想必大家都已经知道了吧。患上精神分裂症之后,大家也不必过于伤心,现在我国的医疗水平是足以让大家快速恢复过来的,所以说一定要保持良好的情绪。

with用法小结

with用法小结 一、with表拥有某物 Mary married a man with a lot of money . 马莉嫁给了一个有着很多钱的男人。 I often dream of a big house with a nice garden . 我经常梦想有一个带花园的大房子。 The old man lived with a little dog on the lonely island . 这个老人和一条小狗住在荒岛上。 二、with表用某种工具或手段 I cut the apple with a sharp knife . 我用一把锋利的刀削平果。 Tom drew the picture with a pencil . 汤母用铅笔画画。 三、with表人与人之间的协同关系 make friends with sb talk with sb quarrel with sb struggle with sb fight with sb play with sb work with sb cooperate with sb I have been friends with Tom for ten years since we worked with each other, and I have never quarreled with him . 自从我们一起工作以来,我和汤姆已经是十年的朋友了,我们从没有吵过架。 四、with 表原因或理由 John was in bed with high fever . 约翰因发烧卧床。 He jumped up with joy . 他因高兴跳起来。 Father is often excited with wine . 父亲常因白酒变的兴奋。 五、with 表“带来”,或“带有,具有”,在…身上,在…身边之意

精神分裂症的病因是什么

精神分裂症的病因是什么 精神分裂症是一种精神方面的疾病,青壮年发生的概率高,一般 在16~40岁间,没有正常器官的疾病出现,为一种功能性精神病。 精神分裂症大部分的患者是由于在日常的生活和工作当中受到的压力 过大,而患者没有一个良好的疏导的方式所导致。患者在出现该情况 不仅影响本人的正常社会生活,且对家庭和社会也造成很严重的影响。 精神分裂症常见的致病因素: 1、环境因素:工作环境比如经济水平低低收入人群、无职业的人群中,精神分裂症的患病率明显高于经济水平高的职业人群的患病率。还有实际的生活环境生活中的不如意不开心也会诱发该病。 2、心理因素:生活工作中的不开心不满意,导致情绪上的失控,心里长期受到压抑没有办法和没有正确的途径去发泄,如恋爱失败, 婚姻破裂,学习、工作中不愉快都会成为本病的原因。 3、遗传因素:家族中长辈或者亲属中曾经有过这样的病人,后代会出现精神分裂症的机会比正常人要高。 4、精神影响:人的心里与社会要各个方面都有着不可缺少的联系,对社会环境不适应,自己无法融入到社会中去,自己与社会环境不相

适应,精神和心情就会受到一定的影响,大脑控制着人的精神世界, 有可能促发精神分裂症。 5、身体方面:细菌感染、出现中毒情况、大脑外伤、肿瘤、身体的代谢及营养不良等均可能导致使精神分裂症,身体受到外界环境的 影响受到一定程度的伤害,心里受到打击,无法承受伤害造成的痛苦,可能会出现精神的问题。 对于精神分裂症一定要配合治疗,接受全面正确的治疗,最好的 疗法就是中医疗法加心理疗法。早发现并及时治疗并且科学合理的治疗,不要相信迷信,要去正规的医院接受合理的治疗,接受正确的治 疗按照医生的要求对症下药,配合医生和家人,给病人创造一个良好 的治疗环境,对于该病的康复和痊愈会起到意想不到的效果。

comparison的用法解析大全

comparison的用法解析大全 comparison的意思是比较,比喻,下面我把它的相关知识点整理给大家,希望你们会喜欢! 释义 comparison n. 比较;对照;比喻;比较关系 [ 复数 comparisons ] 词组短语 comparison with 与…相比 in comparison adj. 相比之下;与……比较 in comparison with 与…比较,同…比较起来 by comparison 相比之下,比较起来 comparison method 比较法 make a comparison 进行比较 comparison test 比较检验 comparison theorem 比较定理 beyond comparison adv. 无以伦比 comparison table 对照表 comparison shopping 比较购物;采购条件的比较调查 paired comp arison 成对比较 同根词 词根: comparing adj. comparative 比较的;相当的 comparable 可比较的;比得上的 adv. comparatively 比较地;相当地 comparably 同等地;可比较地 n.

comparative 比较级;对手 comparing 比较 comparability 相似性;可比较性 v. comparing 比较;对照(compare的ing形式) 双语例句 He liked the comparison. 他喜欢这个比喻。 There is no comparison between the two. 二者不能相比。 Your conclusion is wrong in comparison with their conclusion. 你们的结论与他们的相比是错误的。 comparison的用法解析大全相关文章: 1.by的用法总结大全

With_复合结构详解

介词With 复合结构讲解及练习 with复合结构的作用:with复合结构在句子中作状语,表示原因、时间、条件、伴随、方式等. 1)We sat on the dry grass with our backs to the wall.(作伴随状语) 2)She could not leave with her painful duty unfulfilled.(作原因状语) 3)He lay in bed with his head covered.(作方式状语) 4)Jack soon fell asleep with the light still burning.(作伴随状语) 5)I won't be able to go on holiday with my mother being ill.(作原因状语) 6)He sat with his arms clasped around his knees.(作方式状语) 注:with复合结构在句子中还可以作定语,阅读下面的句子。 1)There was a letter for Lanny with a Swiss stamp on it.(作定语修饰letter) 2)It was a vast stretch of country with cities in the distance.(作定语修饰a stretch of country)1) with +宾语+ 现在(短分词语) When mother went into the house, she found her baby was sleeping in bed, with his lips moving. 当妈妈走进房子的时候,她发现自己的孩子正睡在床上,嘴唇一直在动。 My aunt lives in the room with the windows facing south. 我姑妈住在那间窗户朝南开的房间。 With winter coming on,it's time to buy warm clothes 2)with +宾语+ 过去分词(短语) With more and more forests damaged ,some animals and plants are facing the danger of dying out. 由于越来越多的森林遭到破坏,一些动植物正面临着灭绝的危险。 With his legs broken, he had to lie in bed for a long time. 他双腿都断了,只得长时间躺在床上。 3) with +宾语+ 不定式(短语) * With so many children to look after, the nurse is busy all the time. 有这么多的孩子需要照顾,保育员一直都很忙。 *With a lot of papers to correct, M r. Li didn’t attend the party. 李老师有许多试卷需要批改,所以没有参加聚会。 4) with +宾语+ 副词 * You should read with the radio off. 在看书的时候应该把收音机关掉。 * With the temperature up, we had to open all the windows. 气温上升,我们不得不打开所有的窗户。 5) with +宾语+形容词 *With the window open, I felt a bit cold. 窗户开着,我感到有点冷。 * It was cold outside , the boy ran into the room with his nose red. 外面天气很冷,那个男孩跑进了屋子时,鼻子红红的。 6) with +宾语+ 介词短语 * The woman with a baby in her arms is getting on the bus. 怀里抱着婴儿的那位妇女正在上车。 * John starts to work very clearly in the morning and goes on working until late in the afternoon with a break at midday . 约翰早上开始工作,中午稍作休息后又接着工作到下午稍晚些时候。

with的用法

with[wIT] prep.1.与…(在)一起,带着:Come with me. 跟我一起来吧。/ I went on holiday with my friend. 我跟我朋友一起去度假。/ Do you want to walk home with me? 你愿意和我一道走回家吗 2.(表带有或拥有)有…的,持有,随身带着:I have no money with me. 我没有带钱。/ He is a man with a hot temper. 他是一个脾气暴躁的人。/ We bought a house with a garden. 我们买了一座带花园的房子。/ China is a very large country with a long history. 中国是一个具有历史悠久的大国。3.(表方式、手段或工具)以,用:He caught the ball with his left hand. 他用左手接球。/ She wrote the letter with a pencil. 她用铅笔写那封信。4.(表材料或内容)以,用:Fill the glass with wine. 把杯子装满酒。/ The road is paved with stones. 这条路用石头铺砌。5.(表状态)在…的情况下,…地:He can read French with ease. 他能轻易地读法文。/ I finished my homework though with difficulty. 虽然有困难,我还是做完了功课。6.(表让步)尽管,虽然:With all his money, he is unhappy. 尽管他有钱,他并不快乐。/ With all his efforts, he lost the match. 虽然尽了全力,他还是输了那场比赛。7.(表条件)若是,如果:With your permission, I’ll go. 如蒙你同意我就去。8.(表原因或理由)因为,由于:He is tired with work. 他工作做累了。/ At the news we all jumped with joy. 听到这消息我们都高兴得跳了起来。9.(表时间)当…的时候,在…之后:With that remark, he left. 他说了那话就离开了。/ With daylight I hurried there to see what had happened. 天一亮我就去那儿看发生了什么事。10. (表同时或随同)与…一起,随着:The girl seemed to be growing prettier with each day. 那女孩好像长得一天比一天漂亮。11.(表伴随或附带情况)同时:I slept with the window open. 我开着窗户睡觉。/ Don’t speak with your mouth full. 不要满嘴巴食物说话。12.赞成,同意:I am with you there. 在那点上我同你意见一致。13.由…照看,交…管理,把…放在某处:I left a message for you with your secretary. 我给你留了个信儿交给你的秘书了。/ The keys are with reception. 钥匙放在接待处。14 (表连同或包含)连用,包含:The meal with wine came to £8 each. 那顿饭连酒每人8英镑。/ With preparation and marking a teacher works 12 hours a day. 一位老师连备课带批改作业每天工作12小时。15. (表对象或关系)对,关于,就…而言,对…来说:He is pleased with his new house. 他对他的新房子很满意。/ The teacher was very angry with him. 老师对他很生气。/ It’s the same with us students. 我们学生也是这样。16.(表对立或敌对)跟,以…为对手:The dog was fighting with the cat. 狗在同猫打架。/ He’s always arguing with his brother. 他老是跟他弟弟争论。17.(在祈使句中与副词连用):Away with him! 带他走!/ Off with your clothes! 脱掉衣服!/ Down with your money! 交出钱来! 【用法】1.表示方式、手段或工具等时(=以,用),注意不要受汉语意思的影响而用错搭配,如“用英语”习惯上用in English,而不是with English。2.与某些抽象名词连用时,其作用相当于一个副词:with care=carefully 认真地/ with kindness=kindly 亲切地/ with joy=joyfully 高兴地/ with anger=angrily 生气地/ with sorrow=sorrowfully 悲伤地/ with ease=easily 容易地/ with delight=delightedly 高兴地/ with great fluency =very fluently 很流利地3.表示条件时,根据情况可与虚拟语气连用:With more money I would be able to buy it. 要是钱多一点,我就买得起了。/ With better equipment, we could have finished the job even sooner. 要是设备好些,我们完成这项工作还要快些。4.比较with 和as:两者均可表示“随着”,但前者是介词,后者是连词:He will improve as he grows older. 随着年龄的增长,他会进步的。/ People’s ideas change with the change of the times. 时代变了,人们的观念也会变化。5.介词with和to 均可表示“对”,但各自的搭配不同,注意不要受汉语意思的影响而用错,如在kind, polite, rude, good, married等形容词后通常不接介词with而接to。6.复合结构“with+宾语+宾语补足语”是一个很有用的结构,它在句中主要用作状语,表示伴随、原因、时间、条件、方式等;其中的宾语补足语可以是名词、形容词、副词、现在分词、过去分词、不定式、介词短语等:I went out with the windows open. 我外出时没有关窗户。/ He stood before his teacher with his head down. 他低着头站在老师面前。/ He was lying on the bed with all his clothes on. 他和衣躺在床上。/ He died with his daughter yet a schoolgirl. 他去世时,女儿还是个小学生。/ The old man sat there with a basket beside her. 老人坐在那儿,身边放着一个篮子。/ He fell asleep with the lamp burning. 他没熄灯就睡着了。/ He sat there with his eyes closed. 他闭目坐在那儿。/ I can’t go out with all these clothes to wash. 要洗这些衣服,我无法出去了。这类结构也常用于名词后作定语:The boy with nothing on is her son. 没穿衣服的这个男孩子是她儿子。 (摘自《英语常用词多用途词典》金盾出版社) - 1 -

精神分裂症应该怎么治疗

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