2024屆高考英語二輪詞法專題講座素材：10 情態動詞
英語詞法專題講座十：情態動詞
一．情態動詞的用法
1. can 用法
1）表示能力，與be able to同義，但can只用于現在時和過去時，be able to可用于各種時態。
Two eyes can see more than one.
注：Can you …
?
Yes, I can / No, I can’t.
2). 表示允許、請求
用could比can 語氣更加委婉客氣，常用于could I /you …..? 句型中，若表示同意時，用can回答而不用could.
Could I borrow the book ?
No, you can’t.
3). 表示推測 “可能”常用于否定句或疑問句中。（can’t表示一定不是）
It can’t be true.
Can it be true?
2. may 用法
1）表允許，請求= can
表示許可或征求對方的許可，常于第一人稱連用。
注：May I ….? Yes, you may.
No, you can’t / mustn’t.
在回答以may引起的問句時，多避免用這個詞，而用其它方式，如Yes,
please. / Certainly.
2）表推測，可能、也許。常用于肯定句中。
Maybe he knows the news. =
He _____ _____ the news.
3. must
1）表示義務。意為“必須”（主觀意志）。
We must do everything step by step.
注：Must I ….? Yes, you must / No, you needn’t (don’t have to ).
--Must we hand in our exercise—books now?
--No, you needn’t.
/ No,
you don’t have to.
2）mustn’t 表禁止、不允許。
You mustn’t talk to her like that.
3）表示揣測。意為“想必、準是、一定”等，只用于肯定句。否定、疑問句中must改為can.
He must be ill. He looks so pale.
She’s wearing a diamond necklace. She must have a lot of money.
注：must表推測時，其反義疑問句與must后面的動詞一致。
There must be something wrong, ____ ____?
4. need的用法
need既可用作情態動詞，也可用作實義動詞。用作情態動詞時，主要否定句或疑問句中。用作實義動詞時，可用于各種句式。
1). 用作情態動詞，用于否定句和疑問句中。
a). Need I ….? Yes, you must / No, you needn’t .
Need we finish the work today ? Yes you __?
A. need
B. can
C. may
D. must
b). need + do sth . 變否定句：needn’t do sth
變疑問句：Need sb do sth ?
2). 用作實義動詞
a). need + to do sth .
We need _______(buy) some school things .
變否定句：don’t /doesn’t /didn’t +need to do sth .
變疑問句：Do / Does /Did sb + need to sth ?
Yes , … do/ does / did
No, sb don’t / doesn’t /didn’t.
You don’t need to do it yourself.
b). 當主語是物時。Sth + need + doing sth =
Sth +need to be done .
The table needs painting.
=The table needs _____ _____ _____ .
5. had better 的用法
1). had better + 動詞原形
= It’s best to do sth.
You had better ______ (stay )at home. = _____ ______ ______ stay at home.
2). Had better not +動詞原形
We had better ________(not play ) the computer games.
6. must 與have to
1). 一般情況下，兩者可互換。 must = have to
2). must “必須，應該”表示說話人的主觀看法，即說話人認為必須干某事。
?。▋仍谠颍?/p>
have to “必須，不得不”強調客觀需要，即外界因素迫使某人不得不干某事。（外界原因）
I can’t stop playing the computer games.
For your health, I’m afraid you ______.
A. can
B. may
C. must
D. had to
二．情態動詞后跟完成式和進行式的用法
1. 情態動詞后跟完成式，表“原本應該干某事，而實際上沒干”
I should have finished the work earlier.
He isn’t here. He must have missed the train.
2. 情態動詞后跟進行式，表示“想必正在……”，“可能正在……”，“應當正在”等意。
It’s twelve o’clock. They must be having lunch.
They may be discussing this problem.
He can’t be telling the truth.
She shouldn’t be working like that. She’s still so weak.
三．情態動詞的同義轉換.
1. can = be able to
2. must = have to
3. needn’t = don’t have to
4. need do sth = need to do sth .
英語詞法專題講座十：情態動詞
一．情態動詞的用法
1. can 用法
1）表示能力，與be able to同義，但can只用于現在時和過去時，be able to可用于各種時態。
Two eyes can see more than one.
注：Can you …
?
Yes, I can / No, I can’t.
2). 表示允許、請求
用could比can 語氣更加委婉客氣，常用于could I /you …..? 句型中，若表示同意時，用can回答而不用could.
Could I borrow the book ?
No, you can’t.
3). 表示推測 “可能”常用于否定句或疑問句中。（can’t表示一定不是）
It can’t be true.
Can it be true?
2. may 用法
1）表允許，請求= can
表示許可或征求對方的許可，常于第一人稱連用。
注：May I ….? Yes, you may.
No, you can’t / mustn’t.
在回答以may引起的問句時，多避免用這個詞，而用其它方式，如Yes,
please. / Certainly.
2）表推測，可能、也許。常用于肯定句中。
Maybe he knows the news. =
He _____ _____ the news.
3. must
1）表示義務。意為“必須”（主觀意志）。
We must do everything step by step.
注：Must I ….? Yes, you must / No, you needn’t (don’t have to ).
--Must we hand in our exercise—books now?
--No, you needn’t.
/ No,
you don’t have to.
2）mustn’t 表禁止、不允許。
You mustn’t talk to her like that.
3）表示揣測。意為“想必、準是、一定”等，只用于肯定句。否定、疑問句中must改為can.
He must be ill. He looks so pale.
She’s wearing a diamond necklace. She must have a lot of money.
注：must表推測時，其反義疑問句與must后面的動詞一致。
There must be something wrong, ____ ____?
4. need的用法
need既可用作情態動詞，也可用作實義動詞。用作情態動詞時，主要否定句或疑問句中。用作實義動詞時，可用于各種句式。
1). 用作情態動詞，用于否定句和疑問句中。
a). Need I ….? Yes, you must / No, you needn’t .
Need we finish the work today ? Yes you __?
A. need
B. can
C. may
D. must
b). need + do sth . 變否定句：needn’t do sth
變疑問句：Need sb do sth ?
2). 用作實義動詞
a). need + to do sth .
We need _______(buy) some school things .
變否定句：don’t /doesn’t /didn’t +need to do sth .
變疑問句：Do / Does /Did sb + need to sth ?
Yes , … do/ does / did
No, sb don’t / doesn’t /didn’t.
You don’t need to do it yourself.
b). 當主語是物時。Sth + need + doing sth =
Sth +need to be done .
The table needs painting.
=The table needs _____ _____ _____ .
5. had better 的用法
1). had better + 動詞原形
= It’s best to do sth.
You had better ______ (stay )at home. = _____ ______ ______ stay at home.
2). Had better not +動詞原形
We had better ________(not play ) the computer games.
6. must 與have to
1). 一般情況下，兩者可互換。 must = have to
2). must “必須，應該”表示說話人的主觀看法，即說話人認為必須干某事。
?。▋仍谠颍?/p>
have to “必須，不得不”強調客觀需要，即外界因素迫使某人不得不干某事。（外界原因）
I can’t stop playing the computer games.
For your health, I’m afraid you ______.
A. can
B. may
C. must
D. had to
二．情態動詞后跟完成式和進行式的用法
1. 情態動詞后跟完成式，表“原本應該干某事，而實際上沒干”
I should have finished the work earlier.
He isn’t here. He must have missed the train.
2. 情態動詞后跟進行式，表示“想必正在……”，“可能正在……”，“應當正在”等意。
It’s twelve o’clock. They must be having lunch.
They may be discussing this problem.
He can’t be telling the truth.
She shouldn’t be working like that. She’s still so weak.
三．情態動詞的同義轉換.
1. can = be able to
2. must = have to
3. needn’t = don’t have to
4. need do sth = need to do sth .
