AUT重庆高中一年级英语Unit1Gramma课件重庆大学版 必修2r.ppt

文档介绍：重庆大学版
高一(2)
Unit 1
Grammar
Modal Verbs (Ⅰ)must, may, should, will, have to
Studying the Rule
1) A: It’s hot, isn’t it?
B: Yeah, but it may rain tomorrow.
2) A: May I sit down?
B: No, you mustn’t.
A: Why not?
B: Because it is broken.
3) A: The flight to New York should be leaving in a few minutes.
B: Are you sure?
4) A: Sally, you should be careful when you go out at night.
B: Ok, I will.
5) A: I have just walked 5 minutes!
B: You must be very tired now.
6) A: Will you give this to Elle, please?
B: With pleasure.
7) A: It’s raining cats and dogs outside.
B: Really? Then I have to take an umbrella with me.
8) A: Must I hand in the homework now?
B: No, you don’t have to. You may hand it in tomorrow morning.
6) A: When are we going to leave the hotel?
B: We must leave the hotel before 6 pm.
总结
1. must与have to的区别
have to比较强调客观需要, must着重说明主观看法。另外have to能用于更多时态, 比较下面的句子:
We had to be there at 10:00.
有时两者都可以用, 意思差别不大。
e. g.
We must/have to leave now.
must在表示说话人对事物的推测时候要注意它比may肯定得多, 相当于汉语的“一定”或“准是”。(只有在肯定句中能这样用。)
This must be your room.
在回答由must引起的问题时, 如果是否定的答复,不能用mustn’t, 而需要用needn’t或don’t have to, 因为mustn’t是“一定不要”的意思。