第06讲 疑问词和连词(解析版)

第六讲 疑问词和连词
【课程解读】
————小学初中课程解读————
【知识衔接】
————小学知识回顾————
疑问词
连词
并列连词：连接两个或两个以上地位平等的词、短语或分句。

但是，可是，而，却
和，同，与，又，并且, 然后
句末或句中。

要特别注意标点的使用。

e.g. She felt ill. She went to work, however, and tried to concentrate. Alice is a good student ．However, she has one shortcoming ． The composition is all right. There is room for improvement, however.
e.g. She cut her knee badly, but didn't cry.
I'd love to go to the theatre tonight, but I'm too busy.
He was tired but happy after the long walk.
2. 用于表示歉意的话语之后，表示谢绝或不赞成；
e.g. Excuse me, but could you tell me where the post office is?
I’m sorry, but I have another appointment tonight.
e. g. You've bought the wrong shirt. It's not the red one I wanted but the blue one.
Tom went to the party, but his brother didn't.
4. 含“but”的习惯搭配:
and
1. “和”、“又”、“并且”（相当于also; in addition to）；
e. g. bread and butter 面包和黄油slowly and carefully 缓慢而仔细地
Tidy up your room. And don't forget to make your bed!
She came in and sat down. 她进来以后就坐下了。

【注意】：并列结构中，and用于肯定句，通常否定句用or。

e. g. There is no air or water in the moon.
He can't read or write.
2. “加”（相当于plus），连接两个数字,谓语动词用单数。

e. g. 5 and 5 makes 10. 5加5等于10。

3. 用在祈使句后，表示结果，意为“那么, 就” 。

e. g. Work hard and you will succeed. 努力干吧，你会成功的。

4. 常见搭配：
e. g. go and fetch 去拿come and look at 来看看wait and see 等着瞧吧
and so on等等try and improve. 尽量改进
two thousand, two hundred and sixty four 二千二百六十四
————初中知识链接————
疑问词
疑问词的选择：
1.对指物名词或谓语动词提出疑问，疑问词用what；关于what的其他疑问词：what color…That is my new T-shirt. →What is that?
I am writing a piece of article. →What are you doing?
The shirt is light yellow. →What color is the shirt?
2.对修饰名词的定语提出疑问，疑问词应用which，而且通常和名词连用。

The book on the second shelf is mine. →Which book is yours?
The girl in pink is my classmate. →Which girl is your classmate?
The movie with many movie stars is my favourite one. →Which movie is your favourite one?
3.对指人名词或代词提问用who，作宾语时提问用whom。

That boy is my younger brother. →Who is that boy?
I gave that book to the boy next to me. →Whom / Who did you give that book to?
4.主代词和名词所有格提问用whose。

That computer is his friend Mike’s. →Whose computer is that?
I have lost my toy in Mr. Green’s home.→ Whose toy have you lost in Mr. Green’s home?
5.①具体时间提出疑问，如in the morning, last Sunday等，疑问词用when；
I finished my homework this afternoon. →When did you finished your homework?
②对具体几点钟提问，疑问词应用what time。

I usually get up at 7:30 am. →What time do you usually get up?
6.对具体地点提出疑问，疑问词应用where。

I come from Canada. →Where do you come from?
Alex lived in his hometown during the winter vacation. →Where did Alex live during the winter vacation?
7.对表原因的从句提问，常见的有because引导的从句，疑问词应用why。

I am late for school because my bike broke down on the way. →Why are you late for school? There won’t be a sports meeting because it is going to rain. →Why isn’t there a sports meeting?
I will get up early to catch the early bus tomorrow. →Why will you get up early tomorrow?
8. 对方式或程度等提出疑问，用疑问词How。

I like China very much. →How do you like China?
We can write something with ink. →How can you write something?
My father goes to work on foot every morning. →How does your father go to work every morning?
The boy made the cake by reading the cooking book carefully. →How did the boy make the cake?
9. 对数量提出疑问，疑问词为How many，要注意how many必须跟名词的复数形式。

There are over thirty birds in the tree. →How many birds are there in the tree?
I need some milk before I go to bed. →How much milk do you need before you go to bed?
10. 对价格提出疑问，疑问词用How much。

That pen is fifteen yuan. →How much is that pen?
Ipad mini cost me nearly three thousand. →How much did ipad mini cost you?
11. 对时间、长度提出疑问，疑问词应用How long。

The ruler is 20 cm long. →How long is that ruler?
It takes me two hours to get to school. →How long does it take me to get to school?
I have stayed in Shanghai for over 3 years. →How long have you stay in Shanghai?
I have known him since I started working. →How long have you known hi m?
12. 对时间频率，如once a year, twice a week等提问，疑问词用How often。

I go to school five times a week. →How often do you go to school?
Students have vacations twice a year. →How often do students have vacations?
The Smiths go travelling every other year. How often do the Smiths go travelling?
对具体次数，如once, twice, three times等提问，疑问词用How many times。

I go to school five times a week. →How many times do you go to school?
Students have vacations twice a year. →How many times do students have vacations?
连词
连接两个或两个以上的分句。

表原因的从属连词: “因为”
because的用法：
1.表示的是必然的因果关系，语气较强，通常放在主句之后，若需强调则放在主句之前。

e. g. I did so because I was happy.
2.通常用来回答why提出的问题。

--Why do you look so sad? --Because I have lost my wallet.
3. 在英语里不能将so与because 连用!
e. g. 因为下雨，所以我们呆在家里。

正：Because it was raining, we stayed at home.
正：It was raining, so we stayed at home.
误：Because it was raining, so we stayed at home.
4. because of, 意为“因为”, 是复合介词，其后可接名词或名词性短语等。

e. g. He couldn’t come because of illness. 他因病不能来。

He couldn’t come because he was ill.
【注意】：because of不能直接引导从句或后接that引导的从句。

【考点拓展】since（从属连词，“既然，由于”），as（从属连词，“因为，由于”）；
表让步的从属连词：
❖although/though的用法：
1. 在一般情况下二者可以互换使用，都可与yet, still
e. g. Although he is poor, he’s still happy. 虽然他很穷，他仍然很快乐。

I will try it, though I may fail. 即使我可能失败, 我也要试一下。

【注意】：
①although引导的让步状语从句位于主句之前的情况较多，though引导的让步状语从句可位于主句之前或主句之后。

② though可用于句尾:
We all tried our best. We lost the game, though. 我们都已尽了最大的力量. 不过我们还是输了.
【经典题型】
小学经典题型
疑问词
一、对划线部分提问—基础篇
1. My father and I were waiting for the ferry.__________________________________
2. We followed this man here.__________________________________
3. He lives in New York.__________________________________
4. I usually get up at six. __________________________________
5. I live with parents.__________________________________
6. We took the next ferry.__________________________________
7. This sign means cars and buses mustn't turn right here.
this sign mean?
8.London held the first World Expo in 1851.
did London the first Word Expo?
9.That new blue car is my father’s.
is your father’s?
10.Mrs. Turner asked her son to buy some eggs for supper.
Mrs. Turner ask her son _______?
11. I'm going to take the shirt on the right.
are you going to take?
12.The pupils are having a picnic at the foot of the hill.
the pupils having a picnic?
【答案】1. What were you and your father waiting for?
2. Whom did you follow here?
3. Where does he live?
4. What time do you usually get up?
5. Whom do you live with?
6. Which ferry did we take?
7. What does
8. When…hold
9. Which car
10. What did…to do
11. Which shirt
12. Where are
二、选择正确的单词填空(who, where, when)
1.________ is that pretty girl? She is my sister.
【答案】Who
2.________ are Jack and Tom? They are behind you.
【答案】Where
3.________ do you go to school? I go to school from Monday to Friday.
【答案】When
4.________ has a beautiful flower? John has a beautiful flower.
【答案】Who
5.________ are they? They are my parents.
【答案】Who
6.________ is my mother? She is in the living room.
【答案】Where
7.________ are you going? We are going to the bakery(面包坊).
【答案】Where
8.________do Jim and Wendy play ball? They play ball in the afternoon.
【答案】When
连词
一、单项选择
1.--- Would you like to come to dinner tonight?
--- I'd like to, ___ I'm too busy.
A. and
B. so
C. as
D. but
【答案】D
【解析】but与前面形成转折，符合语意。

而表并列的and，结果的so，原因的as都不符合句意。

2.---Would you like to come to my house for dinner tonight?
---I'd love to，I have lots of work to do．
A. so B or C. and D．but
【答案】D
【解析】考查转折连词。

so(表结果)，or(表选择)，ad(表并列)，but(表转折)，根据句意：“我很乐意去，但我还有一些事要做”可推断选but，表转折。

3.It was very cold and windy, _________ those farmers were working hard on the farm.
A. and
B. or
C. but
D. so
【答案】C
【解析】考查连词的用法。

but表转折，and表并列，or表选择，so表顺接。

根据句意选C。

4. That was a long _______ dull talk.
A. so
B. and
C. so that
D. or
【答案】B
【解析】long和dull是并列关系用and。

5. Charlie took the job, _______ he did it very well.
A. so
B. yet
C. and
D. so that
【答案】C
【解析】他选择这份工作并且做得很好。

6. My grandfather is in his eighties, _______he is still in good health.
A. or
B. but
C. so
D. for
【答案】B
【解析】我爷爷八十岁了，但是他仍然很健康。

7. — It's nothing serious. Just stay in bed for one or two days. _______ take it easy.
— All right.
A. Still
B. And
C. But also
D. But
【答案】B
【解析】在床上休息一到两天，并且放轻松。

8. Think it over_______ you will find a way.
A. or
B. so
C. and
D. that
【答案】C
【解析】仔细考虑然后你就会找到其他方式了。

9. Cooper can _______speak Chinese _______ read and write it.
A. not only, but also
B. both, also
C. not only, and still
D. either, and
【答案】A
【解析】不但会说中文而且会读和写。

10. I would like to go swimming, _______he won't.
A. and
B. for
C. nor
D. but
【答案】D
【解析】我想要去游泳，但是我不会。

初中经典题型
疑问词
一、对划线部分提问—提高篇
1. He goes to school on foot. _________________________________
【答案】How does he go to school?
2. He has only one brother. _________________________________
【答案】How many brothers does he have?
3. I like Jackie Chan’s films very much. ________________________________ 【答案】Whose films do you like very much?
4. The American spacecraft Galileo travelled and worked in space for 14 years.
_________ ________ did the American spacecraft Galileo travel and work in space? 【答案】How long
5. Xiao Cheng didn't go to the farm with us because he was ill.
_________ ________ Xiao Cheng go to the farm with us?
【答案】Why didn’t
6. I paid fifty yuan for the sweater.
_________ ________ did you pay for the sweater?
【答案】How much
7. I've worked in that factory for two years.
_________ ________ ________ you worked in that factory?
【答案】How long have
8. Danny likes Chinese food very much.
_________ ________ Danny________ Chinese food?
【答案】How does…like
二、单项选择
()1.________ you ________ your homework every day?
A. Do; do
B. Do; /
C. /; do
D. Does; do
【答案】A
【解析】every day用一般现在时的一般疑问句用助动词do
()2.—________ do you get up every day?
—At six.
A. How
B. What time
C. What
D. Which
【答案】B
【解析】根据回答at six确定是时间，提问时间的特殊疑问词用what time ()3.—________？
—Eight yuan a kilo.
A. How many a kilo
B. How much is the fish
C. How many do you want
D. Can I help you
【答案】B
【解析】根据回答用提问多少钱的特殊疑问词
()4.________ you ________ some washing last week?
A. Did; do
B. Did; did
C. Does; do
D. Do; do
【答案】A
【解析】last用一般过去时的一般疑问句
()5.—Is there an egg on the table?
—________.
A. Yes, it is
B. Yes, there is
C. No, there aren't
D. Yes, they are
【答案】B
【解析】There be 结构的肯定和否定回答方式
()6.—How can they go to the cinema?
—________.
A. By bus
B. On bus
C. Take bus
D. In bus
【答案】A
【解析】根据特殊疑问词how得知提问方式
()7.____ you ____ shopping this Sunday?
A. Will; go to
B. Are; going
C. Shall; go to
D. Will; goes
【答案】B
【解析】一般疑问句
()8.—________ are his socks?
—They're under the bed.
A. Where
B. What
C. When
D. How
【答案】A
【解析】根据答语用提问地点的特殊疑问词
连词
一、填空题
1. Put on more clothes, _______ you’ll get a cold.
【答案】or
【解析】穿上衣服，不然会很冷。

否则用or
2. Mrs. Smith likes music _______ her husband likes sport.
【答案】but
【解析】表示转折关系。

3. Is this shirt yours _______ his?
【答案】or
【解析】表示选择关系。

4. _______you come to the office now, _______wait for me at home. You decide.
【答案】Either…or
【解析】要么要么，表示选择关系。

5. He was very sick, _______he finished the work on time.
【答案】but
【解析】表示转折。

二、单项选择
1. I decided not to buy frozen dumplings the government said they were safe.
A. because
B. though
C. since
D. or
【答案】B
【解析】尽管政府说安全的但是我也不去买速冻水饺。

2. I can’t understand the sentence there are no new words in it.
A. if
B. until
C. though
D. because 【答案】C
【解析】尽管句子里没有生词我也不理解。

3. the World Expo was over, a lot of visitors still go to the China Pavilion to enjoy themselves and take photos.
A. Although
B. Since
C. When
D.As
【答案】A
【解析】尽管世博会结束了，但是很多游客还去拍照
4. the manager can't make the service better, the shop will soon lose all the customers.
A. When
B. If
C. Because
D. Although 【答案】B
【解析】如果经理不能把服务做好，商店就要关闭了
5. they are brothers, they don't look like each other at all.
A. Because
B. Though
C. When
D. As
【答案】B
【解析】尽管他们是兄弟，但是他们看起来一点也不像
6. the boy is only six years old, he knows more about science than some adults.
A. Though
B. Since
C. Until
D. When 【答案】A
【解析】尽管这个男孩只有6岁，但是他比很多成年人都了解得多
7. I remember Dad was still working at desk it was very late at night.
A. as
B. since
C. though
D. if
【答案】C
【解析】尽管晚上很晚我记得爸爸还在工作
8. Nowadays there are frequent floods global warming becomes more and more serious.
A. so
B. and
C. because
D. but
【答案】A
【解析】现在洪水多，所以全球变暖越来越严重了
9. Liu Wei lost his arms, he practices playing the piano to make his dream come true.
A. Since
B. Although
C. When
D. Because 【答案】B
【解析】尽管刘伟没有了胳膊，他也练习弹钢琴
10. A big earthquake happened in South Island of New Zealand, nobody was killed in it.
A. for
B. but
C. or
D.so
【答案】B
【解析】大的地震发生了，但是没有人遇难。

【实战演练】
————先作小学题——夯实基础————
疑问词
一、对划线部分提问—综合篇
1. The eighty-year-old man looks happy and healthy.(对划线部分提问)
__________ __________ the eighty-year-old man look?
【答案】How does
2. We hold our school sports meeting once a year. (对划线部分提问)
__________ __________ do you hold your school sports meeting?
【答案】How often
3. She has been here since the beginning of last month. （对划线部分提问）
__________ __________ has she been here?
【答案】How long
4. The young hunter made a fire to drive away the wolf. (对划线部分提问)
__________ __________ the young hunter make a fire?
【答案】Why did
5. The lady by the riverside is over 80 years old.（对划线部分提问）
_________ the _________ of the lady by the riverside?
【答案】What’s…age
6. The Olympic Games take place once four years. (对划线部分提问)
__________ __________ do the Olympic Games take place?
【答案】How often
7. Mr. and Mrs. Black have already been to China three times. (对划线部分提问)
__________ __________ times have Mr. and Mrs. Black been to China?
【答案】How many
8. The Shanghai World Expo will last six months.（对划线部分提问）
__________ __________ will the Shanghai World Expo last?
【答案】How long
9. My father enjoys watching sports news in the evening. (对划线部分提问)
__________ does your father enjoy__________ in the evening?
【答案】What…doing
10. The world turns its attention to the World Cup every four years. (对划线部分提问) _________ _________ does the world turn its attention to the World Cup?
【答案】How often
二、用（what time, what color, what day, what）填空。

1. A: ______ _______ is it? B: It is nine o’clock.
【答案】What time
2. A: ______ _______ does your mother get up?
B: My mother gets up at 6:30.
【答案】What time
3. A: ______ _______ do you go to bed? B: I go to bed at 10:00.
【答案】What time
4. A: ______ _______ do Diana and Fiona have supper?
【答案】What time
B: Diana and Fiona have supper at 18:00.
5. A: ______ _______is it? B: It is purple.
【答案】What colour
6. A: ______ _______ is the sky? B: The sky is blue.
【答案】What colour
连词
一、填空题
1.Have a rest and take this medicine, _________ you will be worse.
【答案】or
【解析】休息一下，不然情况会更糟糕
2.This shirt is _______ too big ________ too small for me.
【答案】neither…nor
【解析】衬衫对我来说既不大也不小
3.He was rather tired, _______ he kept on working.
【答案】but
【解析】他太累了，但是他继续工作
4.She must come from Scotland, _______ only the Scotch talk in that way.
【答案】because
【解析】他一定是来自于斯科特兰，因为只有斯科特兰人才会这样说话
5.She is ________ an artist ________ a scientist.
【答案】not only…but also
【解析】她不但是艺术家而且是科学家
二、单项选择题
1. They waited ______ the bus came.
A. as
B. until
C. when
D. by
【答案】B
【解析】他们一直等到公交车来了
2. I really didn't know who is our new English teacher ________ you told me.
A. until
B. after
C. when
D. though 【答案】A
【解析】知道你告诉我才知道英语老师是谁
3. __________ it was so cold, the boy went out without a cap.
A. But
B. When
C. Although
D. Because 【答案】C
【解析】尽管天气很冷，但是男孩出去也没戴帽子
4. You must set off now, ________ you'll miss the train.
A. and
B. while
C. then
D. or
【答案】D
【解析】你现在必须出发了，否则你回错过火车。

5. Every night Li Lei studied hard and did his homework________ 11:30 pm.
A. at
B. since
C. until
D. for
【答案】C
【解析】李磊每天晚上努力学习写作业写到11：30
6. Jim is_________ clever _______ he understands everything.
A. such a, that
B. as, so
C. so, that
D. so, as 【答案】C
【解析】Jim如此聪明以至于他理解所有
7. We don't understand the passage ________ there are some new word s in it.
A. and
B. if
C. though
D. because
【答案】D
【解析】我不理解这篇文章因为有一些新单词
8. _______it was raining heavily, he came on time.
A. Because
B. For
C. Though
D. If
【答案】C
【解析】尽管雨下的很大，但是他也准时回来
9. ________ you lose confidence(信心) , you won't be able to do the work well.
A. What
B. And
C. So
D. If
【答案】D
【解析】如果你失去信心，你就不能做好
10. I'll speak slowly ________ you can understand me.
A. so
B. so that
C. as
D. since
【答案】B
【解析】我会说的慢一些便于你理解
————再战初中题——能力提升————
疑问词
一、阅读理解
One day, Howard Kelly, a poor boy who was selling goods from door to door, found he had no money left. He was, hungry, so he knocked at a house (敲门)and a young woman opened the door. The boy was shy and only asked for a cup of water. But the lady was so kind that she gave him a large glass of hot milk.
Kelly drank it and then asked," How much should I pay you?"
"You don't need to pay," she replied. Kelly thanked her from the bottom of the heart.
Years later, Kelly became a doctor. One day, a woman was sent to his hospital. She had a rare disease. When Dr. Kelly met her in the ward, he recognized her at once--she was the woman who had given him a glass of milk. He swore to do his best to save his life.
The operation was successful, but the fee ( 费用) was high. After looking at the woman's bill, Dr. Kelly wrote something on it, when the woman received the bill, she didn't dare to look at the total fee. However, something on the side of the bill caught her attention(注意). She began to read the following words: Paid in full with one glass of milk. Dr. Howard Kelly
Answer the questions:
1. Why did Howard Kelly knock at a house one day?
【答案】Because he had no money and he wanted to ask for something to eat.
【解析】根据文章第二段第二行得知。

2. What did the lady give the boy?
【答案】A glass of milk.
【解析】根据文章第一段最后一行得知。

3. What was Kelly years later?
【答案】Kelly became a doctor.
【解析】根据文章第四段第一段得知。

4. Where did Kelly meet the lady?
【答案】In a ward.
【解析】根据文章第四段第二行得知。

5. The lady didn't pay the operation fee, did she?
【答案】Yes, she did.
【解析】根据文章最后一段得知。

6. What do you think of Kelly?
【答案】Aspiring, capable, candid.
二、对划线部分提问
1. I will stay with a friendly European family for two weeks. (对划线部分提问)
_______ _______ will you stay with a friendly European family?
【答案】How long
2. Tina has dinner in a restaurant with her family once a month. （对划线部分提问）_______ _______ does Tina have dinner in a restaurant with her family?
【答案】How often
3. My parents go travelling abroad twice a year.(对划线部分提问)
_______ _______ do your parents go travelling abroad?
【答案】How often
4. It’s about 3050 kilometres from Shanghai to Bangkok. (对划线部分提问)
_______ _______ is it from Shanghai to Bangkok?
【答案】How far
5. Joan had a terrible dream about the Great wave last night.(对划线部分提问)
_______ _______ Joan have a terrible dream about the Great wave?
【答案】When did
6. Mum goes shopping in the supermarket nearby four times a week. (对划线部分提问) _______ _______ does Mum go shopping in the supermarket nearby?
【答案】How often
7. A dog will love you faithfully for many years (对划线部分提问)
_______ _______ will a dog love us?
【答案】How long
8. They go to the supermarket to buy some food and drinks for the picnic. (对划线部分提问)
________ ________ they go to the supermarket?
【答案】Why do
9. I have lived here since I was born.(对划线部分提问)
_______ _______ have you lived here?
【答案】How long
10. Arthur got money to pay for the bike by delivering newspapers every day. (对划线部分提问) _______ _______ Arthur get money to pay for the bike?
【答案】How did
11. The old lady has kept this vase since last year. (对划线部分提问)
________ ________has the old lady kept this vase?
【答案】How long
12. China will continue to save energy and reduce pollution this year. (划线提问)
__________will China continue to __________ this year?
【答案】What…do
13. This new Ipod cost him two thousand yuan. ( 对划线部分提问)
________ ________ did this new Ipod cost him?
【答案】How much
14. We visit our grandparents once a month.（对划线部分提问）
_______ _______ do you visit your grandparents?
【答案】How often
15. The Greens are going to stay in Los Angele for two weeks. (对划线部分提问)
_______ _______ are the Greens going to stay in Los Angele?
【答案】How long
16. The new dictionary cost me fifty yuan. (对划线部分提问)
How ________ ________ the new dictionary cost you?
【答案】much did
17. It's twenty minutes' walk from Brown's home to the new cinema.(对划线部分提问)
_______ _______ is it from Brown's home to the new cinema?
【答案】How far
18. I’d like to give you three wishes. (对划线部分提问)
How _________ wishes _________ you like to give me?
【答案】many would
连词
一、用适当的连词填空：
1. She tried hard ___________ she failed.
【答案】though
【解析】尽管她失败了但是她尽力了。

2. Be quick, _________he’ll be angry.
【答案】or
【解析】快点，否则他会饿的。

3. You may _________ do it yourself _______ leave it to me.
【答案】either…or
【解析】你要么自己做，要么让我做。

4. He could read English ________Japanese well.
【答案】and
【解析】他会说英语和日语
5. He didn’t know anything about that ________ he couldn’t tell you. 【答案】so
【解析】他什么也不知道所以没有告诉你。

6. Use your head, _______ you’ll have a way.
【答案】and
【解析】用你的脑子，然后你就有方法了
7. She’s _______ our teacher _______ our friend.
【答案】not only…but also
【解析】她不但是我们的老师而且是我们的朋友
8. Write to me soon, _______I’ll know a lot about you.
【答案】and
【解析】立刻给我写信，然后我就会了解你了
9. He was ill, _________he was taken to the hospital.
【答案】so
【解析】他生病了，所以他被带去医院了。

10. She finished the work quite quickly, ________she didn’t do it very well.
【答案】but
【解析】她迅速的完成了工作，但是做的并不好。

（二）用适当的连词将下列句子合并起来：
1. Mrs. Smith talked to Allan. Allan studied even harder.
【答案】After Mrs. Smith talked to Allan, he studied even harder.
2.I was late for the meeting. I missed the 7:00 bus.
【答案】I was late for the meeting because I missed the 7:00 bus.
3.The Englishman was trying hard. The German gave up.
【答案】The Englishman was trying hard but the German gave up.
4.The students still had their sports meeting. It was raining
【答案】The students still had their sports meeting though it was raining.
5.You have time tomorrow. We’ll wait for you at the school gate.
【答案】If you have time tomorrow, we will wait for you at the school gate.
6. They have known each other. They were very young.
【答案】They have known each other when they were very young.
7. I saw a wallet on the ground. I was walking in the street.
【答案】I saw a wallet on the ground when I was walking in the street.
8. They tried to work out the difficult problem by themselves. They asked the teacher.
【答案】They tried to work out the difficult problem by themselves before they asked the teacher.
9. I will believe it. I see it with my own eyes.
【答案】I will believe it if I see it with my own eyes.
10. We’ll help you. You’re in trouble.
【答案】We’ll help you when you’re in trouble.。