高一英語語法講解之情態(tài)動詞
情態(tài)動詞
1. 情態(tài)動詞的推測表達(dá)
2. 情態(tài)動詞表達(dá)虛擬語氣
3. 某些情態(tài)動詞的特殊用法
知識重點與難點總結(jié)
知識重點：
情態(tài)動詞在表達(dá)推測意義的句子中的運用：
（一）用情態(tài)動詞表達(dá)事實的推測。can，could，might，may，must可以用來表達(dá)對事實的推測。根據(jù)說話人對事實的把握性大小，must表示肯定，may / might / can / could表示可能， must只用于肯定句中，may / might的否定式may not / might not表示 可能不, 而can / could可以用于疑問句，表示可能，可能嗎?，其否定式cant / couldnt 表示不可能。用情態(tài)動詞可以對現(xiàn)在或過去的事實進(jìn)行推測。對不同的時間內(nèi)容推測有不同的結(jié)構(gòu)。
（二）對現(xiàn)在的事實進(jìn)行推測：
主要結(jié)構(gòu)：must / may / might +動詞原形
be+名詞/形容詞/介詞短語
be + doing
例句：
1. You must be Jeanne. Im Mathilde Loisel. We used to know each other very well.
2. They must be in bed already at this time of the night.
3. The teacher must be joking.
4. Freda isnt in class. She must be sick.
5. There must be something wrong.
6. She might be very clever, but she hasnt got much common sense.
7. He may be arriving this evening.
8. He may be traveling around the world.
9. The keys cant be in the room. I have just searched it very carefully.
10. Can the news be true ?
（三）對過去的事實進(jìn)行推測：結(jié)構(gòu)：情態(tài)動詞+have done / been+名詞/形容詞/介詞短語
例句：
1. Mrs. Longmans must have been a pretty girl in her youth.
2. He couldnt have seen Anna yesterday. Shes gone abroad.
3. I think I must have left my glasses in the library.
4. He might have overslept again.
5. Where can Tom have gone ?
情態(tài)動詞表達(dá)虛擬語氣：表達(dá)本來，不然早就。這是情態(tài)動詞的一種虛擬語氣用法。表示說話人所講的與所發(fā)生的事實相反。表達(dá)了說話人的埋怨，后悔的語氣。其結(jié)構(gòu)是在一些情態(tài)動詞后面加 have done 結(jié)構(gòu)。根據(jù)要表達(dá)的意思，有如下結(jié)構(gòu)：
should have done / ought to have done：本應(yīng)該
shouldnt have done / oughtnt to have done：本不該
could have done：本來可以
neednt have done：本來沒必要
would like to have done：本來很想
would rather not have done: 本來不愿意
could / might / have done: 不然早就
例句：
1. You shouldnt have laughed at his mistakes.
2. You could have told us earlier.
3. I ought to have bought that dictionary last week.
4. You ought not to have spent so much time in reading novels.
5. We need not have been in a tearing hurry to catch the train.
6. They would like to have seen that film last film.
7. If he had given me his number, I could have telephoned him.
8. They might have been frozen to death but for the rescue in time.
知識難點：
某些情態(tài)動詞的特殊用法：
need 和dare 的兩種形式的用法
need 和dare可以用做實義動詞，后面接不定式（to do）結(jié)構(gòu)，在疑問句和否定句中，加助動詞do/does/did/或dont/doesnt/didnt。作為情態(tài)動詞使用時，主要用于疑問句和否定句中。情態(tài)動詞neednt（沒有必要，不必）相當(dāng)于dont have to
例句：
1. It is cold, you need to wear some warm clothes.
2. Need I stay here with you for a while ? Thank you, you neednt.
3. How dare you speak to parents like that ?
注意：
句型I dare say+從句。 意思是：我肯定 = Im sure或There is no doubt that+從句。
例句：
I dare say that my uncle will get the money if I die.
will和would
表示意志或愿意，would 則指過去愿意做
例句：
1. He said that he would help us.
2. You may telephone if you will accept this job.
would可以表達(dá)過去習(xí)慣做類似于used to do
例句：
1. When we were children, we would go swimming every summer in that river.
表示請求，固定的句型：Will/Would you please do? / Would you like to do?
例句：Will/Would you please give him a message when you see him ?
shall
1. 用于第一，三人稱，表示請求；建議 或推薦
例句：
1. Shall we start the meeting now?
2. Shall I watch TV now ?
3. Shall my son carry the case for you ?
2. 用于第二人稱，表示命令，要求，許諾
例句：
1. You shall take whatever you like.
2. You shall not go to the party with me if you make so much noise again.
在表示推測的否定句或疑問句中，常用can /cant /could / couldnt表示，意思是：可能嗎?；不可能。而不能使用mustnt或must等詞。
【典型例題】
1. Do you think he will do me a favor ?
As far as I know, he is the last one to help others. He _____ be prepared to give you a hand, though.
A. mightB. must C. canD. should
分析：本題考查情態(tài)動詞推測性用法。 根據(jù)he is the last one to help others.（他是最不可能幫助別人的人），既然如此，那么幫助你的可能性也就最小了。答案為A
2. Look, someone is coming. Guess who it ____ be ?
I think it ___ be Tom.
I dont think it ___ be ____ .
A. can ; must ; can ; heB. may ; can ; must ; him
C. must ; can ; must ; hisD. might ; must ; can ; himself
分析：根據(jù)備選答案。 can表示推測時用于疑問句或否定句中。本題首句就應(yīng)該是Guess who can it be? 第二句應(yīng)該是I think it must be Tom.（說話人十分肯定）。第三句表達(dá)了說話人對前一個人的否定。即：I dont think it can be him/he.（不可能是他）。答案為A
3. Do you know Ms. Wang likes walking after supper ?
Sure. She ____ around the campus now.
A. must be walkingB. must walk
C. may walkD. may be walking
分析：關(guān)鍵詞Sure告訴我們說話人的口氣十分肯定。根據(jù)句子語境：她此刻肯定正在校園散步呢。must be doing表示肯定正在做。答案為A
4. I stayed at a hotel in New York.
Oh, did you ? You _____ with Barbara.
A. could have stayed B. could stay C. would sayD. must have stayed
分析：首句說：我在紐約住在一家賓館里。在此a hotel是泛指。所以D選項不合題意。第二句在說：你本來可以和Barbara.住在一起的。Could have done表示：本來可以。答案為A
5. Why didnt you tell me there was no meeting today ? I _____ all the way here through the heavy snow.
A. neednt have drivenB. cant have driven
C. mustnt have drivenD. shouldnt have driven
分析：根據(jù)句意：你為什么不告訴我今天沒有會？我本來沒必要冒著大雪開車跑這么多路。Neednt have done表示本來沒必要。答案為A
6. I was really anxious about you. You _____ home without a word.
A. mustnt leaveB. shouldnt have left
C. couldnt have leftD. neednt leave
分析：根據(jù)句意：我真的很擔(dān)心你，你真不應(yīng)該一句話都不說就離開家。離開家已經(jīng)發(fā)生了。Should have done正好表達(dá)了本句的意思。答案為B
7. A：Are you coming to Jeffs party ?
B：Im not sure. I _____ go to the concert instead.
A. mustB. would C. shouldD. might
分析：根據(jù)B的回答：我不一定去，我有可能去聽音樂會。Might表示推測：可能。答案為D
8. A：I promise that she ____ get a nice present on her birthday.
B：Will it be a big surprise to her ?
A. should B. mustC. wouldD. shall
分析：A說：我答應(yīng)她在生日聚會上她會得到一份生日禮物。shall表示許諾。答案為D 情態(tài)動詞
1. 情態(tài)動詞的推測表達(dá)
2. 情態(tài)動詞表達(dá)虛擬語氣
3. 某些情態(tài)動詞的特殊用法
知識重點與難點總結(jié)
知識重點：
情態(tài)動詞在表達(dá)推測意義的句子中的運用：
（一）用情態(tài)動詞表達(dá)事實的推測。can，could，might，may，must可以用來表達(dá)對事實的推測。根據(jù)說話人對事實的把握性大小，must表示肯定，may / might / can / could表示可能， must只用于肯定句中，may / might的否定式may not / might not表示 可能不, 而can / could可以用于疑問句，表示可能，可能嗎?，其否定式cant / couldnt 表示不可能。用情態(tài)動詞可以對現(xiàn)在或過去的事實進(jìn)行推測。對不同的時間內(nèi)容推測有不同的結(jié)構(gòu)。
（二）對現(xiàn)在的事實進(jìn)行推測：
主要結(jié)構(gòu)：must / may / might +動詞原形
be+名詞/形容詞/介詞短語
be + doing
例句：
1. You must be Jeanne. Im Mathilde Loisel. We used to know each other very well.
2. They must be in bed already at this time of the night.
3. The teacher must be joking.
4. Freda isnt in class. She must be sick.
5. There must be something wrong.
6. She might be very clever, but she hasnt got much common sense.
7. He may be arriving this evening.
8. He may be traveling around the world.
9. The keys cant be in the room. I have just searched it very carefully.
10. Can the news be true ?
情態(tài)動詞
1. 情態(tài)動詞的推測表達(dá)
2. 情態(tài)動詞表達(dá)虛擬語氣
3. 某些情態(tài)動詞的特殊用法
知識重點與難點總結(jié)
知識重點：
情態(tài)動詞在表達(dá)推測意義的句子中的運用：
（一）用情態(tài)動詞表達(dá)事實的推測。can，could，might，may，must可以用來表達(dá)對事實的推測。根據(jù)說話人對事實的把握性大小，must表示肯定，may / might / can / could表示可能， must只用于肯定句中，may / might的否定式may not / might not表示 可能不, 而can / could可以用于疑問句，表示可能，可能嗎?，其否定式cant / couldnt 表示不可能。用情態(tài)動詞可以對現(xiàn)在或過去的事實進(jìn)行推測。對不同的時間內(nèi)容推測有不同的結(jié)構(gòu)。
（二）對現(xiàn)在的事實進(jìn)行推測：
主要結(jié)構(gòu)：must / may / might +動詞原形
be+名詞/形容詞/介詞短語
be + doing
例句：
1. You must be Jeanne. Im Mathilde Loisel. We used to know each other very well.
2. They must be in bed already at this time of the night.
3. The teacher must be joking.
4. Freda isnt in class. She must be sick.
5. There must be something wrong.
6. She might be very clever, but she hasnt got much common sense.
7. He may be arriving this evening.
8. He may be traveling around the world.
9. The keys cant be in the room. I have just searched it very carefully.
10. Can the news be true ?
（三）對過去的事實進(jìn)行推測：結(jié)構(gòu)：情態(tài)動詞+have done / been+名詞/形容詞/介詞短語
例句：
1. Mrs. Longmans must have been a pretty girl in her youth.
2. He couldnt have seen Anna yesterday. Shes gone abroad.
3. I think I must have left my glasses in the library.
4. He might have overslept again.
5. Where can Tom have gone ?
情態(tài)動詞表達(dá)虛擬語氣：表達(dá)本來，不然早就。這是情態(tài)動詞的一種虛擬語氣用法。表示說話人所講的與所發(fā)生的事實相反。表達(dá)了說話人的埋怨，后悔的語氣。其結(jié)構(gòu)是在一些情態(tài)動詞后面加 have done 結(jié)構(gòu)。根據(jù)要表達(dá)的意思，有如下結(jié)構(gòu)：
should have done / ought to have done：本應(yīng)該
shouldnt have done / oughtnt to have done：本不該
could have done：本來可以
neednt have done：本來沒必要
would like to have done：本來很想
would rather not have done: 本來不愿意
could / might / have done: 不然早就
例句：
1. You shouldnt have laughed at his mistakes.
2. You could have told us earlier.
3. I ought to have bought that dictionary last week.
4. You ought not to have spent so much time in reading novels.
5. We need not have been in a tearing hurry to catch the train.
6. They would like to have seen that film last film.
7. If he had given me his number, I could have telephoned him.
8. They might have been frozen to death but for the rescue in time.
知識難點：
某些情態(tài)動詞的特殊用法：
need 和dare 的兩種形式的用法
need 和dare可以用做實義動詞，后面接不定式（to do）結(jié)構(gòu)，在疑問句和否定句中，加助動詞do/does/did/或dont/doesnt/didnt。作為情態(tài)動詞使用時，主要用于疑問句和否定句中。情態(tài)動詞neednt（沒有必要，不必）相當(dāng)于dont have to
例句：
1. It is cold, you need to wear some warm clothes.
2. Need I stay here with you for a while ? Thank you, you neednt.
3. How dare you speak to parents like that ?
注意：
句型I dare say+從句。 意思是：我肯定 = Im sure或There is no doubt that+從句。
例句：
I dare say that my uncle will get the money if I die.
will和would
表示意志或愿意，would 則指過去愿意做
例句：
1. He said that he would help us.
2. You may telephone if you will accept this job.
would可以表達(dá)過去習(xí)慣做類似于used to do
例句：
1. When we were children, we would go swimming every summer in that river.
表示請求，固定的句型：Will/Would you please do? / Would you like to do?
例句：Will/Would you please give him a message when you see him ?
shall
1. 用于第一，三人稱，表示請求；建議 或推薦
例句：
1. Shall we start the meeting now?
2. Shall I watch TV now ?
3. Shall my son carry the case for you ?
2. 用于第二人稱，表示命令，要求，許諾
例句：
1. You shall take whatever you like.
2. You shall not go to the party with me if you make so much noise again.
在表示推測的否定句或疑問句中，常用can /cant /could / couldnt表示，意思是：可能嗎?；不可能。而不能使用mustnt或must等詞。
【典型例題】
1. Do you think he will do me a favor ?
As far as I know, he is the last one to help others. He _____ be prepared to give you a hand, though.
A. mightB. must C. canD. should
分析：本題考查情態(tài)動詞推測性用法。 根據(jù)he is the last one to help others.（他是最不可能幫助別人的人），既然如此，那么幫助你的可能性也就最小了。答案為A
2. Look, someone is coming. Guess who it ____ be ?
I think it ___ be Tom.
I dont think it ___ be ____ .
A. can ; must ; can ; heB. may ; can ; must ; him
C. must ; can ; must ; hisD. might ; must ; can ; himself
分析：根據(jù)備選答案。 can表示推測時用于疑問句或否定句中。本題首句就應(yīng)該是Guess who can it be? 第二句應(yīng)該是I think it must be Tom.（說話人十分肯定）。第三句表達(dá)了說話人對前一個人的否定。即：I dont think it can be him/he.（不可能是他）。答案為A
3. Do you know Ms. Wang likes walking after supper ?
Sure. She ____ around the campus now.
A. must be walkingB. must walk
C. may walkD. may be walking
分析：關(guān)鍵詞Sure告訴我們說話人的口氣十分肯定。根據(jù)句子語境：她此刻肯定正在校園散步呢。must be doing表示肯定正在做。答案為A
4. I stayed at a hotel in New York.
Oh, did you ? You _____ with Barbara.
A. could have stayed B. could stay C. would sayD. must have stayed
分析：首句說：我在紐約住在一家賓館里。在此a hotel是泛指。所以D選項不合題意。第二句在說：你本來可以和Barbara.住在一起的。Could have done表示：本來可以。答案為A
5. Why didnt you tell me there was no meeting today ? I _____ all the way here through the heavy snow.
A. neednt have drivenB. cant have driven
C. mustnt have drivenD. shouldnt have driven
分析：根據(jù)句意：你為什么不告訴我今天沒有會？我本來沒必要冒著大雪開車跑這么多路。Neednt have done表示本來沒必要。答案為A
6. I was really anxious about you. You _____ home without a word.
A. mustnt leaveB. shouldnt have left
C. couldnt have leftD. neednt leave
分析：根據(jù)句意：我真的很擔(dān)心你，你真不應(yīng)該一句話都不說就離開家。離開家已經(jīng)發(fā)生了。Should have done正好表達(dá)了本句的意思。答案為B
7. A：Are you coming to Jeffs party ?
B：Im not sure. I _____ go to the concert instead.
A. mustB. would C. shouldD. might
分析：根據(jù)B的回答：我不一定去，我有可能去聽音樂會。Might表示推測：可能。答案為D
8. A：I promise that she ____ get a nice present on her birthday.
B：Will it be a big surprise to her ?
A. should B. mustC. wouldD. shall
分析：A說：我答應(yīng)她在生日聚會上她會得到一份生日禮物。shall表示許諾。答案為D 情態(tài)動詞
1. 情態(tài)動詞的推測表達(dá)
2. 情態(tài)動詞表達(dá)虛擬語氣
3. 某些情態(tài)動詞的特殊用法
知識重點與難點總結(jié)
知識重點：
情態(tài)動詞在表達(dá)推測意義的句子中的運用：
（一）用情態(tài)動詞表達(dá)事實的推測。can，could，might，may，must可以用來表達(dá)對事實的推測。根據(jù)說話人對事實的把握性大小，must表示肯定，may / might / can / could表示可能， must只用于肯定句中，may / might的否定式may not / might not表示 可能不, 而can / could可以用于疑問句，表示可能，可能嗎?，其否定式cant / couldnt 表示不可能。用情態(tài)動詞可以對現(xiàn)在或過去的事實進(jìn)行推測。對不同的時間內(nèi)容推測有不同的結(jié)構(gòu)。
（二）對現(xiàn)在的事實進(jìn)行推測：
主要結(jié)構(gòu)：must / may / might +動詞原形
be+名詞/形容詞/介詞短語
be + doing
例句：
1. You must be Jeanne. Im Mathilde Loisel. We used to know each other very well.
2. They must be in bed already at this time of the night.
3. The teacher must be joking.
4. Freda isnt in class. She must be sick.
5. There must be something wrong.
6. She might be very clever, but she hasnt got much common sense.
7. He may be arriving this evening.
8. He may be traveling around the world.
9. The keys cant be in the room. I have just searched it very carefully.
10. Can the news be true ?
