Unit 2 Section Ⅳ Grammar-【金版新学案】2024-2025学年新教材高一英语必修第二册同步课堂高效讲义教师用书word（外研版2019）
Section Ⅳ Grammar
情态动词(Ⅱ)
语法串烧 | 我的发现 |
The new term starts. On campus, there comes a foreign exchange student. From his wearing, we can see he must be from a wealthy family. He also looks very gentle, so he can't be difficult to get along with. Now, he is talking with a student. According to his English accent, I know he may be from US. Last term, there were two exchange students from America in my class. However, I didn't see their names on the class list. I guess that they must have gone back to their country. If this exchange student could be in my class, I will have more chances to practice my spoken English with him. | ①情态动词can, may, must, might, could等后接动词原形可以表示对现在或将来情况的推测； ②这些情态动词后接现在完成时态则可以表示对过去情况的推测。 |
学生用书第51页 |
1．can与could的用法
(1)表示能力(could是过去式)。
My grandmother can do some shopping on the Internet，but she couldn't last year.
我奶奶会网购了，但是去年她还不会。
(2)表示猜测，意为“可能”，一般用于疑问句和否定句(could是过去式)。
Can this news be true?
这则消息是真的吗？
(3)表示请求和许可(could表示更委婉的语气，回答时只能用can)。
—Can/Could I go now?
—Yes，you can.
——我现在可以走了吗？
——是的，可以。
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(4)用于肯定的陈述句中，表示理论上或习惯上的可能性。
As we all know，anyone can make mistakes.
我们都知道，任何人都可能犯错。
(5)习惯用法“cannot...too...”表示“无论怎样……都不过分，越……越好”。有时cannot可用can never替代。
We cannot thank you too much for what you've done for us.对于你们为我们所做的一切，我们怎么感激你们都不为过。
◎巧学活用1——单句语法填空
①I could speak Arabic fluently when I was a child and lived in Morocco. But now, I can just say a few things in the language.
②—I heard they went skiing in the mountains last winter.
—It couldn't_be (not be) true because there was little snow there.
③—Do you know where David is? I couldn't find him anywhere.
—Well, he can't_have_gone (go) far — his coat is still here.
④Mr Smith is on time for everything. How can/_could it be that he was late for the important meeting?
2．may与might的用法
(1)表示允许、许可。might在语气上比may更委婉。以may/might开头的问句在否定回答中要用mustn't/can't。
—May/Might I play the computer games after supper?
—Yes，you may./No，you mustn't/can't.
——晚饭后我可以玩电脑游戏吗？
——是的，可以。/不，不行。
(2)表示把握不大的推测，意为“可能”，用于肯定句。
might语气更加不肯定，指现在或将来，只有在宾语从句中might do /be才表示过去的可能性。
①I think he may come tomorrow.
我认为明天他可能会来。
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②He told me he might be late.
他告诉我他可能会迟到。
(3)may用于祈使句表示祝愿。
May you succeed.祝你成功。
(4)may/might as well最好还是……，不妨……
You might as well do it now.你最好还是现在做吧。
◎巧学活用2——单句语法填空
①He had been working for more than 11 hours. He must be tired after such hard work. He may prefer to get some rest.
②Sorry, I'm late. I may/_might_have_turned (turn) off the alarm clock and gone back to sleep again.
③—Excuse me. Is this the right way to the Children's Palace?
—Sorry, I am not sure.But it might be.
3．must的用法
(1)表示“必须”，语气比should，ought to强烈。其否定形式为mustn't (不准；禁止)。
学生用书第52页 |
You mustn't do that，because you must keep your word.你不能那么做，因为你得遵守诺言。
[名师点津]
以must开头的一般疑问句的肯定回答中要用must，否定回答中要用needn't/don't have to。
—Must I finish the paper today?
—Yes，you must./No，you needn't/don't have to.
——今天我必须完成论文吗？
——是的，你必须。/不，你不必。
(2)表示有把握的肯定推测，只能用在肯定句中，意为“一定；准是”；在否定句、疑问句中要用can't代替。
You have worked hard all day.You must be tired.
辛苦工作了一整天，你一定累了。(对现在情况的推测判断)
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