1、Unit 2 Lets celebrate! Period 2 Using language 知识点梳理知识点梳理 单元语法精讲精练情态动词（二）单元语法精讲精练情态动词（二） I.语法感知语法感知 感知以下课文原句，完成方框下的小题 1That is why Letters from Father Christmas could be the perfect book. 2The children must have been very excited as they opened it. 3The letters were also beautifully illustratedeach
2、must have taken its true author. 4In another letter，Father Christmas complained about how he could not stop his helpers. 5Interestingly，the letters did not contain the usual warnings to children that they might not. 6.we can all share the true spirit of giving at Christmas time. 1以上句子中，句 1、句 4 和句 6
3、中的情态动词表能力。 2句 5 中的情态动词表可能性。 3句 2 和句 3 中的情态动词表猜测，意思是“一定已经发生了”。 II.语法精析语法精析 1can 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 couldnt 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
4、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。 (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 youve done for us.对于你们为我们所做的一切，我们 怎么感激你们都不过
5、分。 2may 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 mustnt/cant。 May/Might I play the computer games after supper? Yes，you may./No，you mustnt/cant. 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。 I think he may come to
6、morrow. 我认为明天他可能会来。 He 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。 3must 的用法 (1)表示“必须”，语气比 should，ought to 强烈。其否定形式为 mustnt (不准；禁止)。 You mustnt do that，because you must keep your word.你不能那么做，因为你得遵守诺言。 温馨提示 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 neednt/dont have to。 Mu
7、st I finish the paper today? Yes，you must./No，you neednt/dont 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 cant 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) (3)表示感情色彩，意为“偏偏；偏要”，常指令人不快的事情。 The car must break down just when I was
8、about to start.我正要出发时车偏偏抛锚了。 4情态动词have done “can/could/may/might/musthave done”表示对过去事情的推测。各情态动词的这种具体用 法如下表： can/could have done 1.过去可能做了(表推测) 2.本能做而未做(表虚拟) should/ought to have done 本该做而未做 may/might have done 1.过去也许做了(表推测) 2.本可能做而未做(表虚拟) must have done 一定已经做了 neednt have done 本不必做而做了 From what you s
9、aid，she must have told you all about it. 从你所说的来看，她一定把一切都告诉你了。 You should have told me earlier or I might have gone with them. 你本应该早点告诉我，不然的话我就会和他们一块去了。 They could have sent up the satellite successfully. 他们本来有能力成功发射这颗卫星的。 You ought to/should have been more careful. 你本应该更小心一些的。 You neednt have told t
10、hem about it. 你本来没有必要告诉他们那件事。 III.高考链接高考链接 A.选词填空（can/could，may/might，must) 1.The expert_ arrive at 9 o clock，but I am not sure. 2.Tom comes from Australia；he_ speak English very well. 3.Mary_ play the violin when she was five. 4.Samuel, the tallest boy in our class，_easily reach the books on the to
11、p shelf. 5.He _break a leg just before we go on holiday. 6. Cant you stay a little longer? Its getting late. I really_ go now.My daughter is home alone. 7.You _be Carol. You havent changed a bit after all these years. 8.You _feel all the training a waste of time，but Im a hundred percent sure later y
12、oull be grateful you did it. 9._I use your mobile phone? 10. If someone had attempted to save him，he _not have drowned. 答答案：案： 1. may 2.can 3.could 4.can 5.must 6.must 7.must 8.may 9.May/Can/Could 10.might B.用适当的情态动词或所给动词的正确形式填空 1I _ come to the party with you，but I am not sure about it. 2I heard yo
13、u bought a new book._ I have a look at it? 3You _ try telephoning Mr Smith; he _ be home now. 4It is a pity that he _ break a leg just before we go on holiday. 5Look！The road is wet.It _(rain) last night. 6Her eyes are red.She _(be) crying last night. 7You _(see) the famous film Wolf Warrior as you
14、know so much about the plot(情 节) 8When I was a child，I _ watch TV whenever I wanted to. 答案：答案： 1.may/might 2.May 3.can；may 4.must 5.must have rained 6.must have been 7.must have seen 8.could C.完成句子完成句子 9I cant find my purse.I _ (可能把它忘在) in the supermarket yesterday， but Im not sure. 10In todays info
15、rmation age，the loss of data _(能引起严重的问题) for a company. 11You_ (一定小心) the camera.It costs！ 12You_ (可能感到) all the training a waste of time，but Im a hundred percent sure later youll be grateful you did it. 13It was so noisy that we _(不能听到) ourselves speak. 答案：答案： 9.could/might have left it 10.can caus
16、e serious problems 11.must be careful with 12.may feel 13.couldnt hear D.单句写作 1他是如此伟大的一个人，我们无论怎样赞扬他都不过分。 _ _ 2祝你在新的一年里好运连连！ _ _ 3他为什么每天偏偏中午弹钢琴呢？ _ _ 4他们一定去过长城，不是吗？ _ _ 5史密斯先生不可能去北京了，因为我刚才在图书馆看见他了。 _ _ 答案：答案： 1.He is such a great man that we cant praise him too much. 2.May you be lucky in the following year! 3.Why must he play the piano at noon every day? 4.They must have been to the Great Wall，havent they? 5.Mr Smith cant have gone to Beijing，for I saw him in the library just now.
