m4u2Grammar情态动词.ppt

M4Unit2 grammar and usage
情态动词
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：
, may, must, should, need. etc 表推测，请求，允诺的用法。
must, shall, should. etc 的特殊用法（上下文的语境）
。
+ have done 的用法。
。
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, can(could) /be able to, may(might), ought to
,dare
(should), will(would).
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，但不能单独作谓语，要和行为动词原形或系动词连用共同构成谓语.
，但没有人称和数（have to除外）的变化。
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熟 读 深 思
（一）.can, could的用法.
读下列句子，归纳总结can/could的用法.
care while fishing! You know not all the children can swim.
could read books in English when he was only five.
总结1. 表能力，翻译为“能够/会”。could是 can的过去式： 表过去的能力。can’t/couldn’t:_________.
若强调经过一番努力后成功做到某事用 was/were able to do .= manage to do = succeed in doing …
不能，不会
He didn’t agree with me at first, but I was able to persuade him.
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--- Look at that man in black! Can it be Mr Black?
--- It can’t be Mr. Black ,for he has gone abroad.
总结2. 表可能性，翻译为“可能/会”。
多用于疑问句或否定句。can’t :___________.
不可能
4. Accident can happen on such rainy days.
Children are lovely, but they can be naughty sometimes.
， 表示偶然发生的可能性，翻译为“有时会”。
5. He never tells the truth. How can you believe such a liar like him?
、疑问句和感叹句中，表示怀疑、惊异或不相信的态度.
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can borrow my bike tomorrow.
Students can't take the book out of the reading-room.
总结5. 表许可，翻译为“可以”，用于否定句，表示不允许，翻译为“不可以”。
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7. You can not be too careful.
= You can not be careful enough.
总结7. can 的****惯用法：
’t/can never /can hardly… too+ adj/adv.
adj/adv+enough
越…就越好./ 再怎样也不为过.
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即时训练
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