人教高中英语语法复习情态动词讲解与练习学案（含答案）.doc

情态动词总结
 I 情态动词的特征：
本身有词义。 不能独立作谓语。 后接动词原形一起构成谓语。 不随人称和数的变化。
II 情态动词各自的基本意义及用法：
1. can 与could用法
对比点
can
could
1、表“能力”
Can you lift this heavy box?
I couldn’t understand what he said at all.
2、表“许可”
You can use a different material instead.
He said I could borrow his bike.
3、“怀疑”
No, no, it can’t be true.
What on earth can this mean?
We thought the story could not be true. How could you be so careless?
4、can与be able to 区别
could代替 can，表示语气更为婉转。
Eg. Could I use your bike?
Yes, I can
can (能够)=be able to(仅表能力时)，但be able to 表示一番努力后，
才能做得到，且有更多的时态。
2.may与 might用法
对比点
may
might
1．表“询问”
May I …?(=Can I …?)
Might I …?(=Could I…?)
(但比用may 更客气)
2.表“允许”
You may take the boy there.
He told me he might come.
(might 与told相呼应)
3．表“可能”“或许”
She may nor like this place.
I’m afraid he might not like this play.
注：
1. May I…?的答语。
2. may可表示期望或祝愿
May you succeed !
3. may (might) 用于目的状语从句。
肯定：Yes, you may.
否定：No, you mustn’t 不行
（语气强硬）
No, you may not 或No, you’d better not.
The emperor gave them some gold in order that they might begin their work at once.
3. must与have to用法
对比点
must
have to
1. 表“必须”
（主观看法）必须；没有过去式，可用于间接引语中。
He told me I must do according to what he said.
（客观需要）不得不，有多种时态。It’s raining heavily, we can’t go now.
2. 疑问句
Must I …? Yes, you must.（一定）
No, you needn’t./ you don’t have to.
(不必)
Do you have to go