2019高考英语《强调句》讲解及练习(附答案)
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| 名称 | 2019高考英语《强调句》讲解及练习(附答案) |  | |
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| 版本资源 | 通用版 | ||
| 科目 | 英语 | ||
| 更新时间 | 2019-04-30 22:56:50 | ||
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强调句专题
强调句型的基本结构是：It is/was + 被强调部分(主语、宾语、宾语补足语或状语等) + that/who +句子的其余部分。
一、连接词。一般说来，如果被强调部分是人时，用连词that或who；被强调的部分是宾语，指人时也可以用whom；如果被强调部分是物，只能用连词that。
It was John and Mike who/that saw Mary in the street last night.
It is Mary whom/ who he often helps .
It was in the street that I met him yesterday.
二、时态。如果原句中谓语动词使用的是现在范畴的时态(一般现在时、现在进行时、现在完成/现在完成进行时、一般将来时、将来进行时、将来完成时等)，用It is...that...。如果原句中谓语动词为过去范畴的时态(一般过去时、过去进行时、过去完成时、过去将来时等)，则用It was...that...。如：
Mary met an old beggar in the street yesterday.
It was Mary who/that met an old beggar in the street yesterday. (强调主语)
It was an old beggar whom/that Mary met in the street yesterday. (强调宾语)
It was yesterday that Mary met an old beggar in the street. (强调时间状语)
It was in the street that Mary met an old beggar yesterday. (强调地点状语)
有时，be前可使用表示推测的情态动词。如：
It must be Peter who has let this secret out.一定是彼得将这个秘密泄露出去的。
It might be last night that they did their homework.他们也许是昨晚做完作业的。
三、 强调含有not until的句子。在强调not until句型时，not 位于until从句前，主句谓语动词作相应变化，即it is(was)+not until从句+that +其它。
It was not until he had finished the work that he went home.
It was not until 12 o’clock last night that my brother came home.
四、强调句的疑问句。强调结构的疑问形式：强调一般疑问句中的某一成分时，要在主句中用一般疑问句的顺序。例如：
Was it you that/who broke the window ?
Was it in the war that he lost his son ?
强调特殊疑问句中的疑问词，其结构模式是：“疑问词+ is/was + it +that...”。它同感叹句的强调模式极其相似，首先将疑问句开头的部分作为强调部分，套入强调结构，然后再将其变为疑问句。例如：
1. Where were you born? → Where was it that you were born?
2. What did you want to see? → What was it that you wanted to see?
3. How many people are being trained for the special work? → How many people is it that are being trained for the special work ?。
五、强调句型中的主谓一致。被强调的成分为原句的主语时，that/who之后的谓语动词应与被强调的名词或代词在人称和数方面保持一致关系，从而选用恰当的动词形式。例如：
It is you who/that are wrong.
It is I who/that am answering the question.
但是如果被强调的部分是人称代词，按理应用人称代词主格形式，但在口语或非正式文体中也可以用其宾格形式，此时that/who的谓语动词要用单数第三人称形式is或was。例如：
It is me who is being asked the favor.
另在It is/was..., not...that...句型中，其谓语动词应与肯定部分的词保持一致关系。例如：
It is my brother, not I that studies in that school.
It is you, not your sister that are in charge of the company.
六、感叹句的强调结构，既要体现强调句型的形式特征，又要体现感叹句的自然语序。例如：
1. How happy he looks! → How happy it is that he looks!
2. What a clever boy he is! → What a clever boy it is that he is!
七、强调句型的鉴别方法及相似句型的辨析
强调句型极易与定语从句、名词性从句、状语从句等相关句型混淆，判断的方法是：强调句型中去掉It is/was…that剩下的部分在语法和意义上仍然是一个完整的句子。如：It was yesterday that I met him. 去掉句中的It was …that 该句为：Yesterday I met him. 句意和语法都非常正确，说明这是一个强调句。而其他句型则不行。
[典例展示]
1. It is the ability to do the job________ matters not where you come from or what you are.
A. one B. that C. what D. it
2. David said that it was because of his strong interest in literature _______ he chose the course.
A. that B. what C. why D. how
3. It is these poisonous products _______ can cause the symptoms of the flu, such as headache and aching muscles.
A .who B. that C .how D .what
4. Why! I have nothing to confess. _______ you want me to say?
A. What is it that B. What it is that C. How is it that D. How it is that
5. It was with great joy _______ he received the news that his lost daughter had been found.
A because B which C since D that
6. An awful accident _______, however, occur the other day.
A. does B. did C. has to D. had to
7. It was not until she got home _______ Jennifer realized she had lost her keys.
A. when B. that C. where D. before
8. It was_______ black home after the experiment.
A. not until midnight did he go B. until midnight that he didn’t go
C. not until midnight that he went D. until midnight when he didn’t go
9. —________that he managed to get the information?
—Oh, a friend of his helped him.
A. Where was it B. What was it C. How was it D. Why was it
10.1) It was 20 years ago ________ the two friends met in Viet Nam.
2) It will be 20 years ________ they meet in Viet Nam.
3) It is 20 years ________ he came to live here.
4) It was 20 years ________ he spent in writing this novel.
5) It was not long ________ the people in Austria took up guns.
6) It was midnight _______ he came back home.
A. when B. before C. since D. That
练习一：
1.—Who are making so much noise in the garden?
A. It is B. They are C. That is D. There are
2. It is _______ he often fails in exams ______ makes his parents worried about him.
A. what; that B. that; what C. that; that D. / ; that
3. It is the protection for the trees _______ really matters, rather than how many trees are planted.
A. what B. that C. 不填 D. which
4. It is _____ my father worked _____ I work now.
A. where, that B. where, when C. that, where D. that, that
5. Was _____ that I saw last night at the concert?
A. it you B. not you C. you D. that you
6. It was ten o’clock _____ he came back home.
A. when B. that C. since D. after
7. It was not until he came back _____ he knew the police were looking for him.
A. which B. since C. that D. before
8.--Where was＿＿＿＿＿＿you picked up the wallet﹖
- -Just near the school gate.
A. it B. it that C. the place D. the place that
9. I must find out why＿＿＿＿＿＿so many students made the same mistake.
A. is it that B. was it which C. it is what D. it was that
10. How many years is it＿＿＿＿＿＿your sister came to work here﹖
A. after B. since C. before D. until
11. Is it in the factory＿＿＿＿＿＿＿＿you visited last week＿＿＿＿＿＿＿＿this kind of car is made﹖
A.／ that B. where when C. where that D.／ when
12.＿＿＿＿It's a long time＿＿＿＿＿＿＿I saw you last.
- -Yes and what a pity since it will be a long time＿＿＿＿＿＿we see each other again.
A. since before B. before since C. until after D. after until
13. It was because of bad weather＿＿＿＿＿＿the football match had to be put off.
A. so B. so that C. why D. that
14.It was his remarks＿＿＿＿＿left me wondering about his real purpose.
A. which B. what C. where D. that
15. -- Was it in 1969＿＿＿＿＿＿the American astronaut succeeded＿＿＿＿＿＿landing on the moon﹖
--- Quite right.
A. when on B. that on C. when in D. that in
16.It was not until 1920＿＿＿＿＿＿regular radio broadcasts began. NMET 95?
A. while B. which C. that D. since
17.＿＿＿＿＿＿is a fact that English is being accepted as an international language. NMET 95?
A. There B. This C. That D. It
18.＿＿＿＿＿was in 1979＿＿＿＿＿I graduated from the university. NMET 98?上海?
A. That that B. It that C .That when D. It when
19. It was for this reason＿＿＿＿＿＿her uncle moved out of New York and settled down in a small village.
A. which B. why C. that D. how
20. It is the protection for the trees＿＿＿＿really matters rather than how many trees are planted.
A. what B. that C.／D. which
14.-- Was that the new comer who walked by﹖＿＿＿＿＿.
A. It must be that B. It must have been C. He must be D. This must have been
15. Our classroom is very clean.Do you nowho＿＿cleanedit﹖
A. was it that B. it was that C. was it who D.he was
16. Now then children. It's high time you＿＿＿＿＿＿and dressed.
A. washed B. should wash C. were washed D. are washed
17.＿＿＿＿＿the people have become the master of their own country＿＿＿＿＿＿＿science can really serve the people.
A. It is only then；that B. It was that；when
C. It is only when；that D. It was when；then
18. It was＿＿＿＿＿＿＿＿＿I met Mr. Green in Shanghai.
A. ten years since B. many years ago that
C. five years until D. Two months when
练习二：
1. ____ was Jane that I saw in the library this morning.
A. It B. He C. She D. That
2.when was it you called me yesterday?
A. until B. that C. then D. so
3. It was on October 1st ____ new China was founded.
A. which B. when C. as D. that
4. Was it because he was ill ____ he asked for leave?
A. and B. that C. that’s D. so
5. It is imagination makes the world colorful, full of vigor and vitality. [2007 上海春]
A．where B．what C．that D．when
6. It _____ we had stayed together for a couple of weeks ____ I found we had a lot in common. [2007 浙江卷]
A. was until; when B. was until; that
C. wasn’t until; when D. wasn’t until; that
7. It is not who is right but what is right ______ is of importance. [2007 重庆卷]
A. which B. it C. that D. this
8.It was on 12 May,2008______the earthquake of Wenchuan county,Sichuan provimce happened.
A.since B.which C.that D.when.
9.It was Alice and her husband who saved the old man,_______?
A.wasn’t it B.was it C.didn’t they D.did they
10.When asked to explain______made his lessons so exciting,the teache kept silent.
A.what it is that B.that what it is C.what is it that D.that what is it
11. Who was it ______ put so many large stones on the road?
A. this B. that
C. he D. she
12. What a silly mistake it is ______ you’ve made!
A. it B. this
C. that D. which
13. It was not until midnight ______ the noise of the street stopped.
A. that B. this
C. since D. at which
14. Was ______ that I met at the railway station the other day?
A. it you B. not you
C. you D. that you
15. It was when she was about to go to bed ______ the telephone rang.
A. since B. as
C. that D. then
16. It may have been at Christmas ______ John gave Mary a handbag.
A. before B. who
C. that D. when
17. Why was ______ that the old woman was sent to prison?
A. he B. it
C. that D. because
18. It was his nervousness in the interview ______ probably lost him the job.
A. which B. since
C. that D. what
19. It was the boy ______ had been in prison ______ stole the money.
A. who, where B. that, how
C. who, that D. that, which
20. It might be I, who ______ caused the accident, who ______ to answer for it.
A. has, is B. have, are
C. has, am D. have, am
21. It was _____ I reached there _____ I began to know something about the matter.
A. until, when B. until, that
C. not until, that D. not when, that
22. It was _____ my father worked _____ I work now.
A. where, that B. where, when
C. that, where D. that, that
23. It was not until he came back ______ he knew the police were looking for him.
A. which B. since
C. that D. before
24. It’s more than half a century ______ the People’s Republic of China was liberated.
A. when B. that
C. since D. after
25. It was not ______ you had explained how ______ I managed to do it.
A. for, that B. until, that
C. for, when D. until, when
[分析诊断]
1. B。首先判断这是强调句型，强调的是主语the ability to do the job，所以选用that。
如果原句中谓语动词为过去范畴的时态(一般过去时、过去进行时、过去完成时、过去将来时等)，则用It was...that...。如：
2. A。这个句子稍微复杂点。Said that 后面的是宾语从句。然后在这个从句里，有一个it is…that的强调句。整个宾语从句意思说：正是因为他对文学有浓厚的兴趣，他才选择了这个课程。
3. B。本题强调主语these poisonous products.
4. A。本句中强调句型对特殊疑问词what 进行强调，去掉强调句型后句子为What do you want me to say?我们可以看到被强调的what 是say 的宾语。
5. D。对状语with this joy 进行强调。
6. B。本题考查助动词do对动词的强调。从the other day (那天)判断整个句子应用过去时态，A、C两项时态错误，D项不合题意，故选B，did可译为“的确，真地”。
7. B。句意：直到他到家的时候，Jennifer才意识到钥匙丢了。until结构时用于强调句式时，要将否定词not移到until前。
8. C。本题是对强调句型与not……until从句的结合考查，把not移至被强调的部分之后，要注意把句子中的动词用过去式。
9. C。根据下文的答语 a friend of his helped him可知上文是强调方式状语。
10. 1) D 2) B 3) C 4) D 5) B 6) A 先分析结构，再分析意思。谨慎试词，防止混淆。1.句强调时间状语，故用that；2.是It…before…句型，时间状语从句，只用before；3. It is a period of time since-clause是固定结构，只用since；4.是强调句型，因spend一词为及物动词，故需要宾语that。此例也可能是定语从句，若为定语从句则which亦可。但强调句和定语从句的意义是不同的。5是It…before…句型，时间状语从句，只用before. 6 是when引导的时间状语从句。
PAGE / NUMPAGES
强调句型的基本结构是：It is/was + 被强调部分(主语、宾语、宾语补足语或状语等) + that/who +句子的其余部分。
一、连接词。一般说来，如果被强调部分是人时，用连词that或who；被强调的部分是宾语，指人时也可以用whom；如果被强调部分是物，只能用连词that。
It was John and Mike who/that saw Mary in the street last night.
It is Mary whom/ who he often helps .
It was in the street that I met him yesterday.
二、时态。如果原句中谓语动词使用的是现在范畴的时态(一般现在时、现在进行时、现在完成/现在完成进行时、一般将来时、将来进行时、将来完成时等)，用It is...that...。如果原句中谓语动词为过去范畴的时态(一般过去时、过去进行时、过去完成时、过去将来时等)，则用It was...that...。如：
Mary met an old beggar in the street yesterday.
It was Mary who/that met an old beggar in the street yesterday. (强调主语)
It was an old beggar whom/that Mary met in the street yesterday. (强调宾语)
It was yesterday that Mary met an old beggar in the street. (强调时间状语)
It was in the street that Mary met an old beggar yesterday. (强调地点状语)
有时，be前可使用表示推测的情态动词。如：
It must be Peter who has let this secret out.一定是彼得将这个秘密泄露出去的。
It might be last night that they did their homework.他们也许是昨晚做完作业的。
三、 强调含有not until的句子。在强调not until句型时，not 位于until从句前，主句谓语动词作相应变化，即it is(was)+not until从句+that +其它。
It was not until he had finished the work that he went home.
It was not until 12 o’clock last night that my brother came home.
四、强调句的疑问句。强调结构的疑问形式：强调一般疑问句中的某一成分时，要在主句中用一般疑问句的顺序。例如：
Was it you that/who broke the window ?
Was it in the war that he lost his son ?
强调特殊疑问句中的疑问词，其结构模式是：“疑问词+ is/was + it +that...”。它同感叹句的强调模式极其相似，首先将疑问句开头的部分作为强调部分，套入强调结构，然后再将其变为疑问句。例如：
1. Where were you born? → Where was it that you were born?
2. What did you want to see? → What was it that you wanted to see?
3. How many people are being trained for the special work? → How many people is it that are being trained for the special work ?。
五、强调句型中的主谓一致。被强调的成分为原句的主语时，that/who之后的谓语动词应与被强调的名词或代词在人称和数方面保持一致关系，从而选用恰当的动词形式。例如：
It is you who/that are wrong.
It is I who/that am answering the question.
但是如果被强调的部分是人称代词，按理应用人称代词主格形式，但在口语或非正式文体中也可以用其宾格形式，此时that/who的谓语动词要用单数第三人称形式is或was。例如：
It is me who is being asked the favor.
另在It is/was..., not...that...句型中，其谓语动词应与肯定部分的词保持一致关系。例如：
It is my brother, not I that studies in that school.
It is you, not your sister that are in charge of the company.
六、感叹句的强调结构，既要体现强调句型的形式特征，又要体现感叹句的自然语序。例如：
1. How happy he looks! → How happy it is that he looks!
2. What a clever boy he is! → What a clever boy it is that he is!
七、强调句型的鉴别方法及相似句型的辨析
强调句型极易与定语从句、名词性从句、状语从句等相关句型混淆，判断的方法是：强调句型中去掉It is/was…that剩下的部分在语法和意义上仍然是一个完整的句子。如：It was yesterday that I met him. 去掉句中的It was …that 该句为：Yesterday I met him. 句意和语法都非常正确，说明这是一个强调句。而其他句型则不行。
[典例展示]
1. It is the ability to do the job________ matters not where you come from or what you are.
A. one B. that C. what D. it
2. David said that it was because of his strong interest in literature _______ he chose the course.
A. that B. what C. why D. how
3. It is these poisonous products _______ can cause the symptoms of the flu, such as headache and aching muscles.
A .who B. that C .how D .what
4. Why! I have nothing to confess. _______ you want me to say?
A. What is it that B. What it is that C. How is it that D. How it is that
5. It was with great joy _______ he received the news that his lost daughter had been found.
A because B which C since D that
6. An awful accident _______, however, occur the other day.
A. does B. did C. has to D. had to
7. It was not until she got home _______ Jennifer realized she had lost her keys.
A. when B. that C. where D. before
8. It was_______ black home after the experiment.
A. not until midnight did he go B. until midnight that he didn’t go
C. not until midnight that he went D. until midnight when he didn’t go
9. —________that he managed to get the information?
—Oh, a friend of his helped him.
A. Where was it B. What was it C. How was it D. Why was it
10.1) It was 20 years ago ________ the two friends met in Viet Nam.
2) It will be 20 years ________ they meet in Viet Nam.
3) It is 20 years ________ he came to live here.
4) It was 20 years ________ he spent in writing this novel.
5) It was not long ________ the people in Austria took up guns.
6) It was midnight _______ he came back home.
A. when B. before C. since D. That
练习一：
1.—Who are making so much noise in the garden?
A. It is B. They are C. That is D. There are
2. It is _______ he often fails in exams ______ makes his parents worried about him.
A. what; that B. that; what C. that; that D. / ; that
3. It is the protection for the trees _______ really matters, rather than how many trees are planted.
A. what B. that C. 不填 D. which
4. It is _____ my father worked _____ I work now.
A. where, that B. where, when C. that, where D. that, that
5. Was _____ that I saw last night at the concert?
A. it you B. not you C. you D. that you
6. It was ten o’clock _____ he came back home.
A. when B. that C. since D. after
7. It was not until he came back _____ he knew the police were looking for him.
A. which B. since C. that D. before
8.--Where was＿＿＿＿＿＿you picked up the wallet﹖
- -Just near the school gate.
A. it B. it that C. the place D. the place that
9. I must find out why＿＿＿＿＿＿so many students made the same mistake.
A. is it that B. was it which C. it is what D. it was that
10. How many years is it＿＿＿＿＿＿your sister came to work here﹖
A. after B. since C. before D. until
11. Is it in the factory＿＿＿＿＿＿＿＿you visited last week＿＿＿＿＿＿＿＿this kind of car is made﹖
A.／ that B. where when C. where that D.／ when
12.＿＿＿＿It's a long time＿＿＿＿＿＿＿I saw you last.
- -Yes and what a pity since it will be a long time＿＿＿＿＿＿we see each other again.
A. since before B. before since C. until after D. after until
13. It was because of bad weather＿＿＿＿＿＿the football match had to be put off.
A. so B. so that C. why D. that
14.It was his remarks＿＿＿＿＿left me wondering about his real purpose.
A. which B. what C. where D. that
15. -- Was it in 1969＿＿＿＿＿＿the American astronaut succeeded＿＿＿＿＿＿landing on the moon﹖
--- Quite right.
A. when on B. that on C. when in D. that in
16.It was not until 1920＿＿＿＿＿＿regular radio broadcasts began. NMET 95?
A. while B. which C. that D. since
17.＿＿＿＿＿＿is a fact that English is being accepted as an international language. NMET 95?
A. There B. This C. That D. It
18.＿＿＿＿＿was in 1979＿＿＿＿＿I graduated from the university. NMET 98?上海?
A. That that B. It that C .That when D. It when
19. It was for this reason＿＿＿＿＿＿her uncle moved out of New York and settled down in a small village.
A. which B. why C. that D. how
20. It is the protection for the trees＿＿＿＿really matters rather than how many trees are planted.
A. what B. that C.／D. which
14.-- Was that the new comer who walked by﹖＿＿＿＿＿.
A. It must be that B. It must have been C. He must be D. This must have been
15. Our classroom is very clean.Do you nowho＿＿cleanedit﹖
A. was it that B. it was that C. was it who D.he was
16. Now then children. It's high time you＿＿＿＿＿＿and dressed.
A. washed B. should wash C. were washed D. are washed
17.＿＿＿＿＿the people have become the master of their own country＿＿＿＿＿＿＿science can really serve the people.
A. It is only then；that B. It was that；when
C. It is only when；that D. It was when；then
18. It was＿＿＿＿＿＿＿＿＿I met Mr. Green in Shanghai.
A. ten years since B. many years ago that
C. five years until D. Two months when
练习二：
1. ____ was Jane that I saw in the library this morning.
A. It B. He C. She D. That
2.when was it you called me yesterday?
A. until B. that C. then D. so
3. It was on October 1st ____ new China was founded.
A. which B. when C. as D. that
4. Was it because he was ill ____ he asked for leave?
A. and B. that C. that’s D. so
5. It is imagination makes the world colorful, full of vigor and vitality. [2007 上海春]
A．where B．what C．that D．when
6. It _____ we had stayed together for a couple of weeks ____ I found we had a lot in common. [2007 浙江卷]
A. was until; when B. was until; that
C. wasn’t until; when D. wasn’t until; that
7. It is not who is right but what is right ______ is of importance. [2007 重庆卷]
A. which B. it C. that D. this
8.It was on 12 May,2008______the earthquake of Wenchuan county,Sichuan provimce happened.
A.since B.which C.that D.when.
9.It was Alice and her husband who saved the old man,_______?
A.wasn’t it B.was it C.didn’t they D.did they
10.When asked to explain______made his lessons so exciting,the teache kept silent.
A.what it is that B.that what it is C.what is it that D.that what is it
11. Who was it ______ put so many large stones on the road?
A. this B. that
C. he D. she
12. What a silly mistake it is ______ you’ve made!
A. it B. this
C. that D. which
13. It was not until midnight ______ the noise of the street stopped.
A. that B. this
C. since D. at which
14. Was ______ that I met at the railway station the other day?
A. it you B. not you
C. you D. that you
15. It was when she was about to go to bed ______ the telephone rang.
A. since B. as
C. that D. then
16. It may have been at Christmas ______ John gave Mary a handbag.
A. before B. who
C. that D. when
17. Why was ______ that the old woman was sent to prison?
A. he B. it
C. that D. because
18. It was his nervousness in the interview ______ probably lost him the job.
A. which B. since
C. that D. what
19. It was the boy ______ had been in prison ______ stole the money.
A. who, where B. that, how
C. who, that D. that, which
20. It might be I, who ______ caused the accident, who ______ to answer for it.
A. has, is B. have, are
C. has, am D. have, am
21. It was _____ I reached there _____ I began to know something about the matter.
A. until, when B. until, that
C. not until, that D. not when, that
22. It was _____ my father worked _____ I work now.
A. where, that B. where, when
C. that, where D. that, that
23. It was not until he came back ______ he knew the police were looking for him.
A. which B. since
C. that D. before
24. It’s more than half a century ______ the People’s Republic of China was liberated.
A. when B. that
C. since D. after
25. It was not ______ you had explained how ______ I managed to do it.
A. for, that B. until, that
C. for, when D. until, when
[分析诊断]
1. B。首先判断这是强调句型，强调的是主语the ability to do the job，所以选用that。
如果原句中谓语动词为过去范畴的时态(一般过去时、过去进行时、过去完成时、过去将来时等)，则用It was...that...。如：
2. A。这个句子稍微复杂点。Said that 后面的是宾语从句。然后在这个从句里，有一个it is…that的强调句。整个宾语从句意思说：正是因为他对文学有浓厚的兴趣，他才选择了这个课程。
3. B。本题强调主语these poisonous products.
4. A。本句中强调句型对特殊疑问词what 进行强调，去掉强调句型后句子为What do you want me to say?我们可以看到被强调的what 是say 的宾语。
5. D。对状语with this joy 进行强调。
6. B。本题考查助动词do对动词的强调。从the other day (那天)判断整个句子应用过去时态，A、C两项时态错误，D项不合题意，故选B，did可译为“的确，真地”。
7. B。句意：直到他到家的时候，Jennifer才意识到钥匙丢了。until结构时用于强调句式时，要将否定词not移到until前。
8. C。本题是对强调句型与not……until从句的结合考查，把not移至被强调的部分之后，要注意把句子中的动词用过去式。
9. C。根据下文的答语 a friend of his helped him可知上文是强调方式状语。
10. 1) D 2) B 3) C 4) D 5) B 6) A 先分析结构，再分析意思。谨慎试词，防止混淆。1.句强调时间状语，故用that；2.是It…before…句型，时间状语从句，只用before；3. It is a period of time since-clause是固定结构，只用since；4.是强调句型，因spend一词为及物动词，故需要宾语that。此例也可能是定语从句，若为定语从句则which亦可。但强调句和定语从句的意义是不同的。5是It…before…句型，时间状语从句，只用before. 6 是when引导的时间状语从句。
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