中考冲刺选择填空精选200题

中考冲刺选择填空精选200题

1. ---You’ve dropped _____ “s’’ in the word “acros’’.

---Oh, ____ letter “s’’ should be doubled like this “across’’.

A. a , a

B. an ,a

C. an ,the

D. the ,the

2. ---May I ______ your dictionary for a while?

---Sorry, I’ve left it at home.

A.borrow

B.lend

C.keep

D.take

3. Those_____ have caught SARS disease must be kept off from us.

A.who

B.which

C./

D.what

4. Roy made several kites ,but _____ of them can fly high in the sky.

A. neither

B.none

C. all

D.most

5. A number of people in Beijing ______ caught SARS and the number of the people who died of SARS _____ reached nearly one hundred so far.

A.has, has

B. have, have

C. have,has

D. has, have

6.---Could you tell me how to improve spoken English ?

---Well,just take every chance to practise ______and don’t be shy.

A. speak

B.to speak

C. speaking

D.spoke

7. ---There’s going to ______ a concert in the hall tonight.

---Yes, and the last performance will be given by Michael Jackson.

A.have

B.give

C.play

D.be.

8. An earthquake _______ Dachaidan County in Qinghai province on the morning of April18.

A.happened

B.rocked

C.took place

D.appeared

9.The children ______ not to play with the fire .

A. are told

B. tell

C. are asking

D.warn

10. ---Do you often get on-line?

---Yes.I ______ most of my time on it .It’s a good way to kill the time.

A.cost

B.spend

C.pay

D.take

11.---Will you please show me how to operate the new machine?

---Sure. It’s a piec e of cake.Now let me tell you _____ to do first.

A.what

B.how

C.whether

D.when

12---My trousers are______ out.

---I’ll buy you a new pair.

A.tried

B. worn

C.wearing

D.sold

13.The rubbish ______we have collected can be recycled.

A.who

B.which

C. this

D.what

14.---The artist has got _____ much work to do that he hardly has time to help his wife with the housework.

---That’s true.Even on Sundays he is busy with his work.

A.too

B.so

C.very

D.such

15.---How long have you ____a cough?

---Ever since last night.

A. got

B. had

C. caught

D. taken

16. ________ Iraqi people were killed in the war which broke out on March 20.

A.Thousand

B. Thousands

C. Thousand of

D. Thousands of

17. I went home and _____ my schoolbag and started to help Mother do the cooking.

A. put off

B. dropped off

C.turned off

D.shut off

18.---He seems _____ ill. Shall we take him to the hospital right now?

---I don’t think it matters. Maybe he’s caught a bit of a cold.

A.terrible

B.terribly

C.even

D.more

19. ---Does the child need any help ?

----No.He is old enough to _____ himself.

A.put on

B.wear

C. take care.

D. dress

20.---This is a really wonderful party with interesting people and great food . ---I’m _____ to hear that you are enjoying yourself.

A.sorry

B. glad

C. afraid

D. sure.

21 ---What are you going to do tomorrow?

----I’m not sure. I____ make a trip to Hanzhou with my girl friend.

A.may

B.maybe

C.will

D.must

22.----The pen writes well though it doesn’t cost much.

---- Let me have a try. So _____.

A.it is

B.it does

C.does it

D.is it

23.The accident happened ______ a freezing winter morning.

A.on

B.in

C.at

D.since

24.---____ the Internet _____ in your school?

---Yes , but the computer in our office has often broken down.

A.Is,used

B.Is,using

C.Does ,use

D.Has ,used

25. There was a phone call for you while you were out and it was _____in English.

A. called

B. rung

C. phoned

D.made

26. The essential needs should _______ to the prisoners of wars（战俘）.

A.offer

B.be offering

C.be offered

D.to be offered

27.---I eat _____ vegetables and ______ meat than I did last year.

----That’s why you’re getting fatter.

A. fewer,more

B.more,less

C.less,more

D.many ,much

28.--- How many times have you _______ from your penfriend since last year?

A.heard

B.received

C.got

D.written

29. .—Do you know the city of Ningbo well ?

—Of course I do. I’ve here for nearly 3 years.

https://www.wendangku.net/doc/1816605450.html,e

B. got

C.arrived

D. been

30.---Sorry .I am late.

---It doesn’t matter.The meeting has ______ for just several minutes

A. begun

B. started

C. been on

D.held

31.---- Is the hen old enough to ____ eggs?

----Yes,it has _____ a lot.

https://www.wendangku.net/doc/1816605450.html,y,laid

B.lie,lain

C.lie,laid

https://www.wendangku.net/doc/1816605450.html,y,lain

32.---Can I take both of the presents?

----No,I’m afraid not.You can take ______ of them.

A.both

B.each

C.either

D.any

33.----Could you tell me _____? I must find him.

----Sorry .I have no idea.But he was here just now .

A.where Tom was

B.where has Tom gone

C.where can I find Tom.

D.where Tom is

34.---It’s necessary and important ______school teachers to teach their students how to get on well with others.

----Yes, you said it.

A. of

B. for

C.from

D.to

35.----I don’t think yo ur team can beat theirs.

----____.But we could if Lin Tao were on the team.

A. No,we can’t

B.Yes ,we can’t

C. Yes,we can

D.No, we can

36. .China has made a great contribution _____ preventing SARS.

A.for

B. to

C.with

D.in

37.----I’m t oo busy_______ to my family often.

---Why not call them instead ?

A.writing

B.to write

C.written

D.write

38.----______ present you’ve bought for me!

----I’m glad you like it.

A.How a

B.What a

C.How

D.What

39.---This is no-smoking zone.Can’t you see the sign?

----Oh ,sorry. I ______ it.

A.haven’t seen

B.won’t see

C.don’t see

D.didn’t see

40.----Will you please let me have a look at the photos taken in the States ? ---Sure .I’ll _____ them to school tomorrow.

A.take

B.carry

C.get

D.bring

41- --We will do what we can ____ourselves this term.

---It’s high time for you to work hard.

A.improve

B.to improve

C.be improved

D.be improving

42---What happened to Tom?

---He was crossing the street ____ a motorbike hit him from behind.

A.while

B.when

C.until

D.because

43---Dad,what’s the sea like?

---Well,it’s large and full of water. It covers about _____ of the earth.

A.one third

B.three quarter

C.three-fourth

D.three quarters

44. ---May I go out for an outing with you tomorrow?

---If your mother______.

A. will let

B. will allow

C.let

D.agrees

45---Would you like ______ some fruit?

---No thanks. I don’t feel like _____ anything now.

A.to have,to eat

B.having, to eat

C. to have , eating

D. having ,eating 46---There can be no life on the earth without water.

---That’s right.Water _____ everywhere.

A.needs

B.is needing

C.is needed

D.needed

47---Were you late ____the meeting?

---No,I arrived there ten minutes______ the meeting started.

A.for, before

B. at, before

C. for ,till

D. at ,after

48---Excuse me,______ I don’t think you can smoke here.

----Sorry I didn’t know this is none-smoking zone.

A. and

B.but

C.so

D.then

49---How many English words had you learned _____ the end of last term?

----Aound 2000,but I’ve forgotten most of them.

A.by

B.at

C.to

D.on

50.---Are you learning art now during your spare time?

----No. I’ve stopped _____ Chinese medicine instead.

A.to learn

B.learning

C.dropping

D.to give up

51.----_____ is your new teacher?

----The one standing under the tree with a dictionary in his hand.

A.Who

B.What

C.Where

D.Which

52.---Do you like being a teacher?

---- Sure.But my parents ____ me to be a doctor when I was a young girl..

A.hoped

B.want.

C. wished

D. expect

53. The result is so ______ that we can hardly believe it.

A.surprising

B.surprised

C.amazed

D.surprise

54.---He was ill and had two weeks ______.

A.of

B.away

C.off

D.out

55.---Did you _____ the first place of the league match?

---Of course we did. We _____ all the other teams.

A.beat, beat

B. beat ,won

C. win, won

D.win, beat.

56.---Sorry _____ being late.

---It doesn’t matter. In fact, you ’re just on time______ it

A.for, for

B.of, for

C.for, with

D.of, with

57.---What he enjoys _____ great and interesting.

---Yes,but it’s dangerous.

A.sounds

B. sounding t

C.sounded

D.to sound

58.---You look _______. What has happened to you?

--- Everyone expected us to win the match, but we lost to the girls.

A. sad

B.sadly C .happy D .angrily

59.---- Did you finish _____ the book?

---- Yes ,I did. Thanks ____ your dictionary, I had a better understanding of it.

A.reading,for

B.reading,to

C.to read, for

D.to read ,to

60.----How ____ is it from here Ningbo to Xi’an?

----It’s about two ____ flight.

A.long, hour’s

B.far,hour’s

C.long, hours’

D.far, hours’

61.---Why did you come back so late today ?

----Because it heavily when the meeting was over. We had to wait until it came to a stop.

A was raining

B .is raining C.rained D.rains

62.----Would you like to give us a talk sometime next week ?

----Sure. But what subject should I ?

A.talk

B.talk about

C. talk with

D.talk to

63.---What did the headmaster _______ at the meeting?

---Sorry.I left the meeting before he _______.

A .say,said

B say,spoke.

C speak,said. D.speak,spoke

64.---What about going to the concert?

---Good idea.Let’s ask Tom_____together with us.

A. go B .going C. to go D. goes

65.----Do you have any fun ______ together with the small children?

----Yes. I’ve experienced nothing other than pleasure.

A to be B. be C. being D. are

66.---There’s hardly anything but some old books in the room,_____?

A isn’t it B.is it C is there D isn’t there

67.----Would you like some tea, please ?

----Yes, I prefer tea sugar.

A .to

B .for C. with D. than

68.----Would you please make the child any more ?

---Sorry,but I didn’t mean to.I just wanted him not to play with the fire.

A don’t, cry

B not, to cry C.don’t, to cry D.not, cry

69.----What useful book !

---Yes, it is. But I find it difficult for me to read.

A.an, very

B.a, too

C. an, too

D. a, quite

70.---Maths isn’t as as Chinese.

---I agree with you. I think Chinese is than any other subject.

A easy, easier

B easier, easier

C easy,harder

D hard, easier

71.---Mum, will you take me to the park tomorrow?

---If it rainy.

A. won’t

B.doesn’t C .isn’t D. won’t be

72.----Zhang Guorong, a HK pop singer, jumped from the top of a building and killed himself.

----What a pity! That’s because he had______ li ving in the world.

A .been fed up with B.been pleased with C.nothing to do with D.been used to

73.---Why don’t you go to the lecture-room and listen to the talk?

---I hear there isn’t in it.

A .something new B.new anything C. anything new D. nothing new

74.----I did badly in the long jump.

---- .

A .Congratulations

B .That’s great C. Well done D. Bad luck

75. Miss Liu asked Tom to read the new words and students to listen to him.

A.other

B.the others

C.others

D.the other

76.---Do you know the result of the race?

---Yes. The winner is a boy Lin Feng from Class 4.

A.100-metres, called

B.100-metre, calling

C.100-metre, called

D.100-metres, named

77. The weather here is quite different that of my hometown.

A .from

B with

C than

D as

78. ---Why not _____ him with his lessons?

---I’ve tried to, but he said he didn’t need any.

A. help

B. to help

C. helping

D. helped

79.----Don’t play the dangerous game any more.

----Sorry! I do it again.

A .can’t B.don’t C.won’t D. mustn’t

80.---English is difficult subject. I even want to drop it.

---You’d better not. I’ll help you it.

A.quite a, with

B. a quite, with

C. a very, for

D.very a, with

81.--- My car has broken down. Would you please send someone to ______?

---Ok, my driver will soon be with you.

A.put me up

B.pick me up

C.drop me off

D.turn me up

82.---I hear a traffic accident happened yesterday. Was it terrible ?

---Yes. A car _____ and all the people in it were badly hurt. But luckily,none of them was killed.

A .fell over

B .fell behind C.fell off D. fell down to

83.There are many teenagers ______ in the lake .

A.swimming .

B.swim. C .swam. D.to swim.

84.---Do you think there are too many new words in this unit ?

---Yes, that’s right. I’ll first.

A. look it up

B. look up them

C. look them up

D. look for them

85.---Something is wrong with the car.

---Don’t worry.I’ll have it _______ soon.

A.fixed

B.mending C .to repair D. to fix

86.—Excuse me, where’s the West Hill Farm, please ?

—Go the forest and the foot of the mountain you will find it .

A.through, at

B.across, at

C.through, under

D. past, under

87._____noisy children ! Go and ask them to keep quiet.

A.How

B.What

C.What a

D.How a

88.I’d like to go abr oad for further study, but I _____afford it.

A .don’t B.wasn’t able to C.can’t D. am not

89.Mr Green living in China though he was born in London.

A.would like

B.wants

C.hates

D.enjoys

90.—Here is a piece of paper for you !

—Oh, thanks. It’s for me to write a long letter on.

A.big enough

B.enough big

C. small enough

D.enough small

91.---Shall we leave for home now?

---No, I ______ here until Tom comes back.

A .won’t wait B.will leave C.will wait D. won’t stay

92.---Excuse me,but do you know the way to the hospital,please?

---Sorry, I don’t know, _____.

A.too B .neither C .either D .also

93.—You’d better work too hard like this.

—I see. You mean working too hard makes one tired and ill.

A.not

B.don't C .not to D.won’t

94.—Football by the British at the beginning of last century.

—That’s probably why football is one of the most popular games in England.

A.was invented

B. invented

C.was inventing

D.invents

95---I tried to make Kate ______ her mind, but I found it hard .

----Well,I saw you_______ that when I went past.

A.change, do

B. change , doing

C.to change, do

D. changes,doing

96.—Must we move to the next room ?

—No, you . You may still live here if you like.

A.mustn’t

B.don’t

C.don’t have to

D.won’t

97.I find interesting to play games with children.

A.that

B.how

C.what

D.it

98. are useful animals.

A.Cow

B.Pig

C.Panda

D. Sheep

99.Be careful when the street.

A.to cross

B.cross

C.you cross

D.you’ll cross

100.Take your time, you’ll make another mistake.

A .then B.and C. if D. or

101.This place is really well worth ______ a second time.

A.to visit

B.visits

C.visiting

D.visited

102----I’m ______ in what _____ you.

----Well,don’t follow suit. Just do what you like.

A. interesting,interests

B.interested ,interests

C.interest,interests

D.interest,interesting

103. ---I think he lives _____ No.386 West St.

---Are you sure _____ that?

A. at ,/

B. in ,of

C. in ,about

D. at ,of

104.Saddam and his followers ______ from Baghdad before the air raids took place.

A.had escaped

B.has escaped

C.was escaping

D.escape

105. ---Have you finished your work yet?

---No,not yet. I think it’ll take _____ ten minutes

A.another

B.other

C.others

D.more

106.If you want to prevent yourself from catching diseases, you must keep your living environment _______.

A.clean

B.to clean

C.cleaning

D.dirty

107. ---How long have you been away from your hometown? ---______two years ago.

A.Since

B.For

C.In

D.From

108.George W.Bush encourages the US soldiers to fight _______ their own country.

A.with

B.against

C.for

D.about

109.The earthquake victims _______ in the hospitals.

A. are well treated

B. are taken good care

C. treated

D. are well treating 110.---Tom won the first prize in the competition.

---He ______ it because he is the most hard-working student.

A.needs

B.deserves

C.is sure of

D.should get

111.Most of the deserts ______ to be covered with bushes and trees.

https://www.wendangku.net/doc/1816605450.html,ed

B.were used

https://www.wendangku.net/doc/1816605450.html,e

D.got used

112.The hospital is doing its best to____the patients with the best treatment and services.

A.offer

B.give

C.provide

D.serve

113.Many SARS patients _______ and are allowed to leave the hospitals.

A.have been healed

B.have healed

C.are healed

D.healed

114. Listen,can you hear someone ______ for help?

A.to cry

B.cry

C.crying

D.cries

115.The beautiful scenery ______ tourists to Guilin from the world over.

A. attracts

B. attacks

C. causes

D. catches

116.The PRC was ______ on October 1st 1949.

A.found

B.find

C.founding

D.founded

117. ____the help of the computer, information can ____every corner of the world quickly.

A.With, arrive

B. With, reach

C.Under, arrive

D. Under,reach

118.My mother ______ a second-hand camera for me.

A.gave

B.showed

C.passed

D.bought

119.--- How _____ do you think the war will come to a stop?

---I’m not sure, maybe in another month’s time.

A. long

B. soon

C. often

D. far

120. The boy put his money in his inside pocket,_______he?

A. doesn’t

B. didn’t

C.won’t

D.isn’t

121.He used the money he first made _____ a used bike for himself.

A.buying

B.buy

C. to buy

D.bought

122.Here’s a shirt of Size 70. Would you please try_____?

A.on it

B.try out it

C.try it on

D.try it out

123.This pair of socks is worn out.I’ll have to buy a new ______.

A.one

B.ones

C.pair

D.pairs

124.---_____is your father?

---A doctor in a local hospital..

A.Who

B.Where

C.How

D.What

125.The Smiths live in ______ building. They use a lift to go up and down.

A.a 8-story

B.a 8-stories

C.an 8-stories

D.an 8-story

126.No matter _____ you do, you must do it as well as possible.

A.what

B.how

C.when

D.where

127.We like him not only because he teaches us _____but aslo he treats us ______.

A.good,friendly

B.good,kindly

C.well,friendly

D.well,kindly

128.My father prefers to stay at home rather than ______ on May Day.

A.travel

B.to travel

C. travelling

D.travels

129. ---The rain came to a stop the night before.The fields are still full of water. ---It _____ for nearly a week.

A. had rained

B. has rained

C. would rain

D. was raining

130.The moonlight shone ______ the window and fell on my bed.

A.from

B.on

C.through

D.across

131.--- Could you please tell me the way to the station?

---Sorry,I’m a stranger too.You ______ ask the policeman over there.

A.must

B.may

C.need

D.should

132.You’ve made ______ mistakes this time than ever before.

A.few

B.litlle

C.fewer

D.less

133.Travelling by air is ______ more expensive than by train even though the air tickets are on discount（打折）.

A.very

B.a lot of

C.many

D.far

134.Though the price of the camera is OK, ______ I don’t think I’ll take it.

A.but

B.and

C.yet

D.so

135.The city is trying to ______ the living environment of the people.

A.improve

B.rise

C.lift

D. increase

136.---What was the score of the match? Did you beat them?

---________. We lost to the girls.

A.Sorry, I don’t know

B.I don’t want to talk about it

B.It’s a secret D.Don’t ask me

137.--______ is the population of the town?

---Over 20,000 .And a third of the population ____ workers of the car factory.

A. What, are

B. How many , are

C. What , is

D. How many, is

138---Alice,why didn’t you come here yesterday?

---I ____ , but my son suddenly fell ill and I had to take him to the hospital.

A.had

B.did

C.was going to

D.didn’t

139.---Could I speak to Tom, please?

---Sorry, he isn’t here at the moment. He _______Hangzhou on business .

A.went to

B.has gone to

C.goes to

D.has been to

140.---Good luck to you _____ your trip!

---Thank you _____ your kind words.

A.to, for

B.with, to

C. with, for

D. to, for

141.---So many kinds of shirts! I really don’t know _____.

A. what to buy

B.which to buy

C.to buy which

D. to choose which

142.By the time I got to the check-out, I realized that I had _____ my purse at my office.

A.forgotten

B.left

https://www.wendangku.net/doc/1816605450.html,id

D.put

143.Don’t shout in public, my boy, please,______?

A.won’t you

B.don’t you

C.do you

D.will you

144.---My computer doesn’t work at all.

---Don’t worry.I think I can put it ______for you.

A.well

B.right

C.good

D.up

145.I turned back only to find myself ______ by a group of beggars.

A.follow

B.following

C.to follow

D.followed

146.As soon as the _____news came into our ears,we all cheered and became ______.

中考化学易错题精选-除杂分离和提纯练习题含答案解析

一、中考初中化学除杂分离和提纯 1．除去下列物质中混有的少量杂质（括号内为杂质），拟定的实验方案可行的是 （） A．木炭粉（CuO）——在空气中灼烧 B．KCl溶液（CaCl2）——通入过量的CO2气体，过滤 C．NaCl溶液（Na2CO3）——加入适量的澄清石灰水，过滤 D．H2气体（HCl气体）——依次通过足量的NaOH溶液和浓硫酸 【答案】D 【解析】 【分析】 除杂质的要求是：要把杂质除去，但不能除去需要的物质更不能带入新的杂质。 【详解】 A、木炭粉会与氧气反应生成二氧化碳，不但氧化铜没有除去，还把需要的物质除去了，选项A不正确； B、通入的二氧化碳不能与氯化钙反应，不能除去氯化钙，选项B错误； C、氢氧化钙与碳酸钠反应生成碳酸钙沉淀和氢氧化钠，虽然把碳酸钠除去了，但是带入氢氧化钠这种新的杂质，选项C错误； D、氯化氢气体溶于水形成盐酸，盐酸与氢氧化钠溶液反应生成氯化钠和水，水蒸汽通过浓硫酸后会被浓硫酸吸收，选项D正确。故选D。 2．除去下列各物质中少量杂质，所选用的试剂和操作方法均正确的是（） A．A B．B C．C D．D 【答案】C 【解析】 【分析】

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中考化学选择题精选

中考化学选择题100精选月日 1、下列除杂（括号内的是杂质）所选试剂合理的是（） A、Cu(Zn) 稀盐酸 B、CO2气体(HCl) 氢氧化钠溶液 C、CuO(Cu) 浓硫酸 D、Na2SO4溶液(Na2CO3) 氯化钡 2、除去下列物质中的少量杂质，所用试剂(括号内的物质)不正确的是（） A、氮气中的氧气(铜) B、二氧化碳气体中的水蒸气(浓硫酸) C、碳酸钙中的氯化钠(水) D、氯化钠溶液中的碳酸钠(硫酸)

7、不能用于区别稀硫酸和氢氧化钠溶液的是（） A、紫色石蕊试液 B、NaCl溶液 C、BaCl2溶液 D、CuSO4溶液 8、下列物质中，不能用来鉴别CO和CO2的是（） A、澄清石灰水 B、观察颜色 C、灼热的氧化铜 D、紫色的石蕊试剂 9、某生在化学晚会上表演如下魔术：用毛笔蘸取一种无色液体在一张白纸上书写了“化学魔术”四字，然后再喷上一种无色液体，白纸上立即出现了红色的“化学魔术”四字。该生先后所用的无色液体可能是1 / 14 （） A、石蕊溶液、稀硫酸 B、酚酞溶液、“雪碧”饮料 C、NaOH溶液、酚酞溶液 D、CuSO4溶液、NaOH溶液 10、为了区别O2与CO2两瓶(或两种)无色气体，下列方法中不可行的是（） A、分别通入紫色石蕊溶液中 B、用燃着的木条分别伸入瓶中 C、分别倒入少量NaOH溶液，振荡 D、用塑料可乐瓶分别盛满上述两种气体，各倒入1/5容积的水，盖紧瓶盖，振荡 11、下列实验装置或实验操作不正确的是（）

12、下列变化不能通过一步反应实现的是（） A、Cu→Cu(OH)2 B、Zn→Ag C、CaCl2→CaCO3 D、Na2CO3→NaOH 13、把氧化铜和铁粉的混合物加到一定量的盐酸中，搅拌让他们充分反应后，过滤。取滤液加入少量铁粉，无任何现象。则下列判断正确的是（） A、滤渣中不含铜 B、滤渣可能是铜和铁的混合物 B、滤液中含FeCl2和CuCl2 D、滤液中含FeCl2和HCl 14、实验室里用氯化钾固体配制一定溶质质量分数的氯化钾溶液时，下列仪器中，不必用到的是（） A、托盘天平 B、烧怀 C、量筒 D、漏斗 15、下列实验操作中，正确的是（）

2018年全国各地中考数学选择、填空压轴题汇编(四)

2018年全国各地中考数学选择、填空压轴题汇编（四） 参考答案与试题解析 一?选择题（共18小题） 1. （2018?杭州）如图，已知点P是矩形ABCD内一点（不含边界），设/ PAD=0i, / PBA=0 2,Z PCB=0 3,Z PDC=0 4,若/ APB=8C°，/ CPD=50，贝9（） A .( 0i+M) — (伦+依)=30°B.(他+M) — ( 0i+釘=40 C. ( 0i+ E2)-( (3+ (4) =70° D. ( 0i+ E2) + ( (3+(4) =180 解：??? AD // BC，Z APB=80， ???/ CBP=Z APB -Z DAP=80 -(， ABC( 2+80 —(， 又???△ CDP 中，Z DCP=180 —Z CPD—Z CDP=130 —(， ???Z BCD( 3+130°—(， 又???矩形ABCD 中，Z ABC + Z BCD=180， ?- (+800— (+(+130°- (=180° 即((+() — ( (+() =30°, 故选：A.

2.（2018?宁波）如图，在△ ABC 中，Z ACB=90，Z A=30°，AB=4，以点B 为

圆心，BC 长为半径画弧，交边AB 于点D ，贝A 匚的长为（ ） ???/ B=60° , BC=2 故选：C . （2018?嘉兴）如图，点C 在反比例函数y± （x >0）的图象上，过点C 的直 A ，B ,且AB=BC ，△ AOB 的面积为1,贝U k 的值为 B. 2 C . 3 D . 4 解：设点A 的坐标为（a ，0）， ???过点C 的直线与x 轴，y 轴分别交于点A, B , 且AB=BC ，△ AOB 的面积为1, k ???点 C （-a , —）， ???点B 的坐标为（0, “二） 解得，k=4, 故选：D . X2 27T 180 = _ 5 ???「的长为 B . y 解：???/ ACB=90 , AB=4，/ A=30° , D 'J n 3. 线与x 轴，y 轴分别交于点 A .吉n A . 1