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初中英语连词题20套(带答案)含解析一、初中英语连词1．I've wanted to read Peter Pan for long, _________ today I finally borrowed the book from the library.A. orB. butC. andD. since【答案】 C【解析】【分析】句意：我一直想读《彼得潘》，今天我终于从图书馆借到了这本书。
A或者、否则；B但是，C和；D自从，句子前后是并列关系，则应用连词and，故选C。
【点评】此题考查联系辨析。
根据两句之间的关系确定所使用的连词。
2．You like football ___________ she likes reading.A. WhenB. orC. becauseD. while【答案】 D3．Giveme your email address, _______I'll send you the form.A. orB. andC. butD. nor【答案】 B4．Some people won't realize the importance of their health ____ they lose it.A. becauseB. afterC. whenD. until【答案】 D5．You will find it useful to learn to study by yourself _____ you go to college.A. whileB. untilC. SinceD. when【答案】 D6．Mark felt very bad today. __________, he kept working all day and said nothing about it.A. HoweverB. ThereforeC. OtherwiseD. Besides【答案】 A7．_____________ my brother arrived in Thailand, he visited the local biggest temple at once.A. As soon asB. WhileC. UntilD. Before【答案】 A8．He is getting fat, _______________ he has decided to go to work on foot.A. becauseB. thoughC. soD. and【答案】 C9．Study hard, _______ our parents will be disappointed.A. andB. butC. orD. because【答案】 C10．__________ the teacher came in, the students stopped reading at once.A. WhenB. WhileC. BeforeD. /【答案】 A11．Some people waste food___________ others haven't enough.A. whileB. duringC. whenD. which【答案】 A12．A recent survey shows that 44 percent of Americans want to use self-driving cars, _________ 34 percent believe that they will make the roads mote dangerous.A. althoughB. becauseC. if【答案】 A【解析】【分析】句意：一个近来的调查显示44%的美国人想要使用无人驾驶车，尽管34%的人相信它们会让道路更加危险。
【英语】初中英语连词解析版汇编含解析(1)一、初中英语连词1．A recent survey shows that 44 percent of Americans want to use self-driving cars, _________34 percent believe that they will make the roads mote dangerous.A. althoughB. becauseC. if【答案】 A【解析】【分析】句意：一个近来的调查显示44%的美国人想要使用无人驾驶车，尽管34%的人相信它们会让道路更加危险。
A. 尽管；B. 因为；C. 如果，根据两句的关系可知是让步状语从句，although：尽管，故选A。
【点评】考查连词辨析，根据语境确定两句的关系，选出合适的连词。
2．——What do you think of our school basketball team?——They're going to lose the match __________ they improve their skills.A. unlessB. untilC. ifD. as【答案】 A3．—My parents are crazy about Running Man. How about your parents?—_________ my dad _________ my mum likes it. Instead, they prefer The Voice of China.A. Neither; norB. Both; andC. Not only; but also【答案】 A4．____it rained a lot, we enjoyed our holiday.A. AlthoughB. BecauseC. UnlessD. However【答案】 A5．Giveme your email address, _______I'll send you the form.A. orB. andC. butD. nor【答案】 B6．He knows a lot, ________ he is just a child.A. howeverB. thoughC. andD. because【答案】 B7．Some people won't realize the importance of their health ____ they lose it.A. becauseB. afterC. whenD. until【答案】 D8．How can we improve our environment a lot each of us does something useful for it?A. whileB. untilC. afterD. unless【答案】 D9．Although she is under great stress, ______ she always wears a smile on her face.A. andB. orC. butD. /【答案】 D10．_____________ my brother arrived in Thailand, he visited the local biggest temple at once.A. As soon asB. WhileC. UntilD. Before【答案】 A11．My father was preparing for his speech ______________ my mother was doing some washing last night.A. ifB. unlessC. whileD. until【答案】 C12．She got up very early that day __________ she could catch the first train.A. becauseB. ifC. thoughD. so that【答案】 D13．Jim has been in the factory for two months ________ he left school.A. whenB. sinceC. as soon asD. whether【答案】 B14．This is the most important task should be finished soon.A. whichB. whatC. thatD. /【答案】 C15．Love your parents __________ they are alive. Don't wait until it is too late.A. whileB. thoughC. becauseD. unless【答案】 A【解析】【分析】句意：当你父母活着时爱他们。
（英语）初中英语连词解题技巧(超强)及练习题(含答案)及解析一、初中英语连词1．A recent survey shows that 44 percent of Americans want to use self-driving cars, _________34 percent believe that they will make the roads mote dangerous.A. althoughB. becauseC. if【答案】 A【解析】【分析】句意：一个近来的调查显示44%的美国人想要使用无人驾驶车，尽管34%的人相信它们会让道路更加危险。
A. 尽管；B. 因为；C. 如果，根据两句的关系可知是让步状语从句，although：尽管，故选A。
【点评】考查连词辨析，根据语境确定两句的关系，选出合适的连词。
2．—Why do many kids spend more time playing computer games?—Because their parents are _____ busy _____ they have little time to stay with their children. A. too, to B. so, that C. such, that D. enough, to【答案】 B3．It won't be a long time ________ your son comes back. Don't be worried.A. sinceB. asC. beforeD. unless【答案】 C4．—Tom, what does "Stay hungry, stay foolish." mean?—You can have your own understanding. But I think it means follow your original aspiration （初心） you will succeed.A. soB. butC. andD. or【答案】 C5．—My parents are crazy about Running Man. How about your parents?—_________ my dad _________ my mum likes it. Instead, they prefer The Voice of China.A. Neither; norB. Both; andC. Not only; but also【答案】 A6．Giveme your email address, _______I'll send you the form.A. orB. andC. butD. nor【答案】 B7．He knows a lot, ________ he is just a child.A. howeverB. thoughC. andD. because【答案】 B8．You will find it useful to learn to study by yourself _____ you go to college.A. whileB. untilC. SinceD. when【答案】 D9．—Mom, I want to be an engineer when I grow up.—Son, your dream will not come true _____ you keep trying your best.A. whenB. whetherC. unlessD. because【答案】 C10．—The air pollution is terrible.—It will be worse ______ we take action to protect the environment.A. ifB. unlessC. untilD. when【答案】 B11．—Could you tell me more about the movie Frozen II __________ you have watched it. —No problem. But you'd better watch it in person __________ I can't express its beauty.A. since; soB. unless; asC. since; as【答案】 C12．—Learning to love is like learning to walk.—Yes, ______ we step out bravely, we'll find it's not so difficult.A. as a resultB. even thoughC. as long asD. as far as【答案】 C13．The situation is becoming more serious ________________ we do something to save the Earth.A. ifB. whenC. becauseD. unless【答案】 D14．It is hard to review the knowledge we learn in class ___________ we take notes.A. ifB. unlessC. whenD. after【答案】 B15．Little Kate went to school___________ it rained heavily yesterday.A. thoughB. ifC. butD. since【答案】 A16．He doesn't feel ___________, ___________ he has to see a doctor.A. good enough: butB. well enough; butC. good enough; soD. well enough; so【答案】 D【解析】【分析】句意：他觉得不舒服，所以他必须去看医生。
【英语】英语连词试题(有答案和解析)含解析一、初中英语连词1．Cathy is afraid of the dog. She will run away ____she sees it.A. ever sinceB. althoughC. as soon asD. so that【答案】 C【解析】【分析】句意：凯西害怕狗。
她以看见狗就逃走。
A.自从；B.虽然、即使；C.一……就；D.以便。
这是一个主从复合句，挖空处后引导一个时间状语从句，连词用as soon as，一……就，故答案选C。
【点评】考查连词辨析。
注意选项的意思和用法。
2．You like football ___________ she likes reading.A. WhenB. orC. becauseD. while【答案】 D3．—Why do many kids spend more time playing computer games?—Because their parents are _____ busy _____ they have little time to stay with their children. A. too, to B. so, that C. such, that D. enough, to【答案】 B4．—My parents are crazy about Running Man. How about your parents?—_________ my dad _________ my mum likes it. Instead, they prefer The Voice of China.A. Neither; norB. Both; andC. Not only; but also【答案】 A5．Giveme your email address, _______I'll send you the form.A. orB. andC. butD. nor【答案】 B6．The film is really exciting. the students their teacher is enjoying the film.A. Both; andB. Not only; but alsoC. Either; orD. Neither; nor【答案】 B7．Some people won't realize the importance of their health ____ they lose it.A. becauseB. afterC. whenD. until【答案】 D8．You will find it useful to learn to study by yourself _____ you go to college.A. whileB. untilC. SinceD. when【答案】 D9．How can we improve our environment a lot each of us does something useful for it? A. while B. until C. after D. unless【答案】 D10．Although she is under great stress, ______ she always wears a smile on her face.A. andB. orC. butD. /【答案】 D11．__________ the teacher came in, the students stopped reading at once.A. WhenB. WhileC. BeforeD. /【答案】 A12．Jim has been in the factory for two months ________ he left school.A. whenB. sinceC. as soon asD. whether【答案】 B13．___________three fourths of the Earth's surface is covered with water, 97 percent of it issalt water in the sea.A. ButB. AlthoughC. AsD. However【答案】 B14．My mother has little interest in football ___________ she didn't watch the live match on TV yesterday evening.A. soB. ifC. thoughD. when【答案】 A15．Your spoken English will get better and better ______________ you practise speaking more.A. beforeB. ifC. thoughD. until【答案】 B【解析】【分析】句意：如果你多练习说英语，你的英语口语会越来越好。
（英语）中考英语连词试题(有答案和解析)一、初中英语连词1．I've wanted to read Peter Pan for long, _________ today I finally borrowed the book from the library.A. orB. butC. andD. since【答案】 C【解析】【分析】句意：我一直想读《彼得潘》，今天我终于从图书馆借到了这本书。
A或者、否则；B但是，C和；D自从，句子前后是并列关系，则应用连词and，故选C。
【点评】此题考查联系辨析。
根据两句之间的关系确定所使用的连词。
2．It won't be a long time ________ your son comes back. Don't be worried.A. sinceB. asC. beforeD. unless【答案】 C3．I think you should be against the situation, ________, of course, you are happy with it. A. because B. however C. anyway D. unless【答案】 D4．——What do you think of our school basketball team?——They're going to lose the match __________ they improve their skills.A. unlessB. untilC. ifD. as【答案】 A5．Some people won't realize the importance of their health ____ they lose it.A. becauseB. afterC. whenD. until【答案】 D6．You will find it useful to learn to study by yourself _____ you go to college.A. whileB. untilC. SinceD. when【答案】 D7．Although she is under great stress, ______ she always wears a smile on her face.A. andB. orC. butD. /【答案】 D8．_____________ my brother arrived in Thailand, he visited the local biggest temple at once.A. As soon asB. WhileC. UntilD. Before【答案】 A9．He is getting fat, _______________ he has decided to go to work on foot.A. becauseB. thoughC. soD. and【答案】 C10．She got up very early that day __________ she could catch the first train.A. becauseB. ifC. thoughD. so that【答案】 D11．Yesterday morning I was just leaving the telephone rang.A. whenB. whileC. becauseD. since【答案】 A12．Emily, you are playing video games again! Study hard, ______ you will fail in the coming exam.A. thenB. soC. andD. or【答案】 D【解析】【分析】句意：Emily，你又玩游戏！努力学习，否则你将在接下来的考试中失败。
【英语】英语连词解题技巧及练习题(含答案)及解析一、初中英语连词1．I've wanted to read Peter Pan for long, _________ today I finally borrowed the book from the library.A. orB. butC. andD. since 【答案】 C【解析】【分析】句意：我一直想读《彼得潘》，今天我终于从图书馆借到了这本书。
A 或者、否则；B但是，C和；D自从，句子前后是并列关系，则应用连词and，故选C。
【点评】此题考查联系辨析。
根据两句之间的关系确定所使用的连词。
2．___________ you know the answer, please ___________ your hand.A. If; raiseB. If; riseC. Unless; raiseD. Unless; rise 【答案】 A3．You like football ___________ she likes reading.A. WhenB. orC. becauseD. while 【答案】 D4．This is the most important task should be finished soon.A. whichB. whatC. thatD. /【答案】 C5．You will find it useful to learn to study by yourself _____ you go to college.A. whileB. untilC. SinceD. when【答案】 D6．Mark felt very bad today. __________, he kept working all day and said nothing about it.A. HoweverB. ThereforeC. OtherwiseD. Besides 【答案】 A7．—The air pollution is terrible.—It will be worse ______ we take action to protect the environment.A. ifB. unlessC. untilD. when【答案】 B8．Although she is under great stress, ______ she always wears a smile on her face.A. andB. orC. butD. /【答案】 D。
（英语）初中英语连词答题技巧及练习题(含答案)含解析一、初中英语连词1．I've wanted to read Peter Pan for long, _________ today I finally borrowed the book from the library.A. orB. butC. andD. since【答案】 C【解析】【分析】句意：我一直想读《彼得潘》，今天我终于从图书馆借到了这本书。
A 或者、否则；B但是，C和；D自从，句子前后是并列关系，则应用连词and，故选C。
【点评】此题考查联系辨析。
根据两句之间的关系确定所使用的连词。
2．——What do you think of our school basketball team?——They're going to lose the match __________ they improve their skills.A. unlessB. untilC. ifD. as【答案】 A3．—My parents are crazy about Running Man. How about your parents?—_________ my dad _________ my mum likes it. Instead, they prefer The Voice of China.A. Neither; norB. Both; andC. Not only; but also【答案】 A4．The film is really exciting. the students their teacher is enjoying the film.A. Both; andB. Not only; but alsoC. Either; orD. Neither; nor【答案】 B5．Mark felt very bad today. __________, he kept working all day and said nothing about it.A. HoweverB. ThereforeC. OtherwiseD. Besides【答案】 A6．My wallet dropped on the ground ________________ I was walking.A. beforeB. afterC. whileD. because【答案】 C7．My father was preparing for his speech ______________ my mother was doing some washing last night.A. ifB. unlessC. whileD. until【答案】 C8．Peter bought some goldfish ______________ he found it difficult to raise them.A. becauseB. orC. thoughD. until【答案】 C9．__________ the teacher came in, the students stopped reading at once.A. WhenB. WhileC. BeforeD. /【答案】 A10．She got up late, __________ she missed the bus.A. soB. becauseC. thoughD. but【答案】 A11．You'll have a great time ______________ you go to the party.A. soB. ifC. although【答案】 B【解析】【分析】句意：如果你去参加聚会，你会玩得很开心的。
【英语】中考英语连词专项训练100(附答案)及解析一、初中英语连词1．I've wanted to read Peter Pan for long, _________ today I finally borrowed the book from the library.A. orB. butC. andD. since【答案】 C【解析】【分析】句意：我一直想读《彼得潘》，今天我终于从图书馆借到了这本书。
A或者、否则；B但是，C和；D自从，句子前后是并列关系，则应用连词and，故选C。
【点评】此题考查联系辨析。
根据两句之间的关系确定所使用的连词。
2．—Why do many kids spend more time playing computer games?—Because their parents are _____ busy _____ they have little time to stay with their children.A. too, toB. so, thatC. such, thatD. enough, to【答案】 B3．It won't be a long time ________ your son comes back. Don't be worried.A. sinceB. asC. beforeD. unless【答案】 C4．Giveme your email address, _______I'll send you the form.A. orB. andC. butD. nor【答案】 B5．They waited ____ it was dark before leaving, ____ they didn't want anyone to see them leave.A. since; becauseB. until; asC. unless; butD. so; because【答案】 B6．—Mom, I want to be an engineer when I grow up.—Son, your dream will not come true _____ you keep trying your best.A. whenB. whetherC. unlessD. because【答案】 C7．Mark felt very bad today. __________, he kept working all day and said nothing about it.A. HoweverB. ThereforeC. OtherwiseD. Besides【答案】 A8．—Could you tell me more about the movie Frozen II __________ you have watched it.—No problem. But you'd better watch it in person __________ I can't express its beauty.A. since; soB. unless; asC. since; as【答案】 C9．Although she is under great stress, ______ she always wears a smile on her face.A. andB. orC. butD. /【答案】 D10．My father was preparing for his speech ______________ my mother was doing some washing last night.A. ifB. unlessC. whileD. until【答案】 C11．The situation is becoming more serious ________________ we do something to save the Earth.A. ifB. whenC. becauseD. unless【答案】 D12．You can take___________ the train___________ the bus there. It will take the same amount of time.A. eithers orB. both andC. neither; norD. not only: but also【答案】 A13．Some people waste food___________ others haven't enough.A. whileB. duringC. whenD. which【答案】 A14．My mother has little interest in football ___________ she didn't watch the live match on TV yesterday evening.A. soB. ifC. thoughD. when【答案】 A15．_________ we didn't win the basketball game, we were satisfied with our hard work.A. IfB. ThoughC. SinceD. Because【答案】 B【解析】【分析】句意：虽然我们没有赢得篮球赛，但我们对我们的努力感到满意。
初中英语连词解题技巧(超强)及练习题(含答案)及解析一、初中英语连词1．Tony has learned a lot about Chinese culture ______________ he came to China.A. beforeB. sinceC. untilD. when【答案】 B【解析】【分析】句意：自从来到中国托尼学到很多关于中国文化的东西。
before在……之前；和过去完成时连用；since自从，后跟表示过去的时间状语和现在完成时连用；until直到……才……；不和完成时连用，when当……时候；和过去完成时连用。
故选B。
【点评】连词辨析。
掌握每个连词的使用规则。
2．This is the most important task should be finished soon.A. whichB. whatC. thatD. /【答案】 C3．It was the middle of the night _____the sound of the piano woke me up.A. becauseB. ifC. whenD. although【答案】 C4．He knows a lot, ________ he is just a child.A. howeverB. thoughC. andD. because【答案】 B5．Although she is under great stress, ______ she always wears a smile on her face.A. andB. orC. butD. /【答案】 D6．My wallet dropped on the ground ________________ I was walking.A. beforeB. afterC. whileD. because【答案】 C7．Tom's father was cleaning the car _______________ his mother was doing housework.A. althoughB. asC. sinceD. while【答案】 D8．He is getting fat, _______________ he has decided to go to work on foot.A. becauseB. thoughC. soD. and【答案】 C9．__________ the teacher came in, the students stopped reading at once.A. WhenB. WhileC. BeforeD. /【答案】 A10．She got up late, __________ she missed the bus.A. soB. becauseC. thoughD. but【答案】 A11．Little Kate went to school___________ it rained heavily yesterday.A. thoughB. ifC. butD. since【答案】 A12．Some people waste food___________ others haven't enough.A. whileB. duringC. whenD. which【答案】 A13．Love your parents __________ they are alive. Don't wait until it is too late.A. whileB. thoughC. becauseD. unless【答案】 A【解析】【分析】句意：当你父母活着时爱他们。
【英语】初中英语试卷分类汇编英语连词(及答案)含解析一、初中英语连词1．I've wanted to read Peter Pan for long, _________ today I finally borrowed the book from the library.A. orB. butC. andD. since 【答案】 C【解析】【分析】句意：我一直想读《彼得潘》，今天我终于从图书馆借到了这本书。
A 或者、否则；B但是，C和；D自从，句子前后是并列关系，则应用连词and，故选C。
【点评】此题考查联系辨析。
根据两句之间的关系确定所使用的连词。
2．It won't be a long time ________ your son comes back. Don't be worried.A. sinceB. asC. beforeD. unless 【答案】 C3．—Tom, what does "Stay hungry, stay foolish." mean?—You can have your own understanding. But I think it means follow your original aspiration （初心） you will succeed.A. soB. butC. andD. or 【答案】 C4．—Mom, I want to be an engineer when I grow up.—Son, your dream will not come true _____ you keep trying your best.A. whenB. whetherC. unlessD. because【答案】 C5．Although she is under great stress, ______ she always wears a smile on her face.A. andB. orC. butD. /【答案】 D6．My father was preparing for his speech ______________ my mother was doing some washing last night.A. ifB. unlessC. whileD. until【答案】 C7．Peter bought some goldfish ______________ he found it difficult to raise them.A. becauseB. orC. thoughD. until 【答案】 C8．__________ the teacher came in, the students stopped reading at once.A. WhenB. WhileC. BeforeD. /【答案】 A9．Little Kate went to school___________ it rained heavily yesterday.A. thoughB. ifC. butD. since【答案】 A10．______________ you use your dictionary often, your spelling will improve.A. WhetherB. IfC. ThoughD. While【答案】 B【解析】【分析】句意：如果你经常使用字典，你的拼写就会变好。
（英语）初中英语连词试题(有答案和解析)含解析一、初中英语连词1．—Li Ming, are you leaving for Hangzhou for your trip tomorrow?—No. It will be three days _______ I start my trip.A. afterB. asC. beforeD. when 【答案】 C【解析】【分析】句意：——黎明，你明天动身前往杭州旅行吗？——不，三天后我才开始旅行。
固定句式，it be+时间段+before，……过了多久才……，故选C。
【点评】考查连词辨析，固定句式it be 段时间before…。
2．It is hard to review the knowledge we learn in class ___________ we take notes.A. ifB. unlessC. whenD. after【答案】 B3．—In shopping centers of most foreign countries, we can see many products made in China. —What we need is ________ "Made in China", ________ "Created in China". There is still a long way to go.A. both…andB. not only…but alsoC. neither…norD. either…or 【答案】 B4．—My parents are crazy about Running Man. How about your parents?—_________ my dad _________ my mum likes it. Instead, they prefer The Voice of China.A. Neither; norB. Both; andC. Not only; but also【答案】 A5．It was the middle of the night _____the sound of the piano woke me up.A. becauseB. ifC. whenD. although【答案】 C6．Mark felt very bad today. __________, he kept working all day and said nothing about it.A. HoweverB. ThereforeC. OtherwiseD. Besides 【答案】 A7．—Could you tell me more about the movie Frozen II __________ you have watched it.—No problem. But you'd better watch it in person __________ I can't express its beauty.A. since; soB. unless; asC. since; as【答案】 C8．I got up at six this morning _____________ I could catch the early bus to Nanjing.A. soB. thatC. in order toD. so that 【答案】 D9．The situation is becoming more serious ________________ we do something to save the Earth.A. ifB. whenC. becauseD. unless【答案】 D10．___________three fourths of the Earth's surface is covered with water, 97 percent of it issalt water in the sea.A. ButB. AlthoughC. AsD. However 【答案】 B11．You'd better travel around Nanjing with a local tour guide ______________ you want to know more about its culture.A. unlessB. untilC. althoughD. if【答案】 D【解析】【分析】句意：如果你想了解南京的文化，最好带着当地的导游游览一下。
A：unless除非；B： until 直到……才（为止）；C： although 尽管；D： if如果。
导游带领游览是了解南京的条件，因此要用从属连词if，故选D。
【点评】考查连词辨析。
理解连词的词义和用法，根据前后句的关系，选择正确的连词。
12．______________ China has been a member of WTO, English is more important.A. SinceB. ThoughC. WhenD. If 【答案】 A【解析】【分析】句意：自从中国加入WTO后，英语就更重要了。
since自从，though虽然；when当……时候；if如果，只有since是正确的，though放在此处句子翻译不通顺；when不和现在完成时连用；if引导从句是一般现在时或现在完成时，主句用将来时，故选A。
【点评】考查连词辨析。
根据句意确定所使用的连词。
13．In summer, food will go bad quickly we put it into a fridge.A. ifB. unlessC. as soon asD. when 【答案】 B【解析】【分析】句意：在夏天，食物会很快的变质，除非我们把它放进冰箱里。
if 如果；unless除非；as soon as一……就……while当……的时候。
根据常识可知在夏天食物放在冰箱才不会马上变质，此处是unless引导的条件状语从句，故选B。
【点评】此题考查连词辨析。
弄清所给连词意思，然后根据上下文的联系确定所使用的连词。
14．Tom won't play computer games __________ he finishes his homework.A. ifB. so thatC. unlessD. although 【答案】 C15．—When will the railway that connects the two cities open?— next year. Only half been completed.A. Until; hasB. Not until; hasC. Until; haveD. Not until; have【答案】 B【解析】【分析】句意：——连接两个城市的铁路什么时候会开通？——直到明年。
只完成了一半。
until意为“直到……为止”，通常与延续性动词连用；not until意为“直到……才”，常与短暂性动词连用，这里的句意为，直到明年才开通，故第一空用not until；第二空的half指的是half the railway，主语为the railway，谓语动词应用单数，因此填has，故选B。
【点评】考查连词和主谓一致。
注意识记until和主谓一致的用法。
16．My best friend and I haven't seen each other ___________ she went to the USA 10 years ago.A. whenB. ifC. althoughD. since【答案】 D【解析】【分析】句意：自从我的朋友十年前去了美国，我和我的朋友们就没有见过面。
A.当……时候；B.如果；C.尽管；D.自从。
本句为时间状语从句，主句为现在完成时，从句为一般过去时，因此使用since。
故答案是D。
【点评】考查连词辨析，注意since连接的时间状语从句，主句为现在完成时，从句为一般过去时。
17．Drink more water and go to bed early, _______________ you'll feel better tomorrow. A. and B. or C. if D. unless【答案】 A【解析】【分析】句意：多喝水早睡觉，明天你将感觉更好。
祈使句+and+句子，表示顺承；祈使句+or+句子，表示转折。
多喝水早睡觉就会感觉更好，前后句表示顺承，所以用and，故选A。
【点评】考查祈使句用法，注意平时识记祈使句+and/or+句子。
18．________ you sit in front of the computer all day while working, you'd better take exercisefor at least an hour every day.A. Even ifB. Even thoughC. SinceD. As if 【答案】 C【解析】【分析】句意：既然你整天坐在电脑前工作，你最好每天锻炼至少一小时。
A. Even if 即使，一般引导的是把握不大或假设的事情； B. Even though即使，引出的是事实；C. Since由于，表已知的事实或显见的原因； D. As if 好像，引导表语从句或引导方式状语从句；从文字的表层意思推断，根据you sit in front of the computer all day while working你整天坐在电脑前工作，表示已知的事实，判断空格用since，故选C。
【点评】考查连词辨析。
弄清所给短语意思，根据上下文的联系确定所使用的连词短语。
19．A ship is safe if it stays in a harbor. But this is not ________ it is built for.A. whatB. howC. whyD. where【答案】 A【解析】【分析】句意：如果船停在港湾里是安全的，但这不是它被造的目的。
for介词后面跟代词作宾语。
A. what什么；B. how怎样，表方式； C. why为什么，表原因； D. where 在哪里，表地点；根据but的表达的句意转折，可知造船的目的不是为了安全地停在港湾，由此推断空格是表目的，for what=why，故选A。
