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（一）情态动词
【知识点1】情态动词的基本概念
情态动词是一种本身有一定的词义，表示说话人的情绪，态度或语气的动词，但不能单独作谓语，只能和其他动词的原形构成谓语。
情态动词主要有下列：can (could), may (might), must, need, shall (should), will (would)。
【知识点2】情态动词的特征
1、有一定的词义，但不能单独做谓语，必须和行为动词和系动词连用构成谓语。
2、无人称和数的变化（have to例外，如在一般现在时态下用于第三人称单数时用has to）。
3、后接动词原形，即不带to的不定式。
4、具有助动词的作用，可用来构成否定句、疑问句及用于简单答语。
例：① I cannot swim very well.
② —Can you swim very well? — Yes, I can. / No, I can’t.
【知识点3】can
1、can表示能力
例：I can speak a little Japanese.（我会说一点儿日语。）
2、can表示允许，准许，这时can与may可以互换
例：---Can/May I borrow your bike tomorrow? 明天我可以借你的自行车吗？
---Yes, of course. You can/may use my bike tomorrow. 当然可以。明天你可以用我的自行车。
3、can表示客观可能性，用在否定句和疑问句中表示猜测。
例：①He cannot/can’t be there. 他不可能在那儿。
②Can this news be true ? 这消息可能真实吗？
4、could是can的过去式，在口语中经常代替can，表示非常委婉的请求。这时could和can没有时间上的差别。
例：①Could/Can you tell me if he will go tomorrow? 你能告诉我他明天是否去吗？
②Could/Can I ask you something if you are not busy? 如果您不太忙，我能否问您一些事情？
【知识点4】may和might
1、may表示“准许”和“许可”，这时可与can替换。
例1：—May I smoke here? 我可以在这儿抽烟吗？ —Yes, you may. / Yes, you can. 请抽吧。 —No, you can"t. / No, you mustn"t. / No, you"d better not. 请不要抽烟。2、may表示说话人的猜测，认为某事“可能” 发生，常用于肯定句。
例：---Where’s John? 约翰在哪儿？
---He may be at the library. 他可能在图书馆。
3、might除表示may的过去式外，在口语中还常代替may, 表示非常委婉的请示或实现的可能性较小。这时might和may没有时间上的差异。
例：①Might (May) I speak to you for a few minutes? 我现在可以与你谈几分钟话吗？
②Might I have a photo of your family? 我可以要一张你们的合家照吗？
【知识点5】must和have to
1、must表示说话人的主观意志，表示义务、命令或必要、应当和必须等。现在式与过去式同形。否定句中用mustn’t 表示禁止。
例：①I must go to school today. 今天我必须上学去。
②He told me I mustn’t leave until my mother came. 他告诉我，在我母亲回来之前我不许离开。
2、must表示推测，“一定是”、“准是”，一般用于肯定句。否定句中can’t表示“不可能”。
例：①They must be very tired. Let them have a rest. 他们一定是非常疲劳了。让他们休息一会儿吧。
②Jack doesn’t look well. He must be ill. 杰克看上去气色不太好。他一定是病了。
③Jane’s light is on. She must be at home. She can’t be out. 简的房间里开着灯。她一定在家，不会出去的。
3、以must开头的疑问句，肯定回答用must；否定回答则常用needn’t，意为“不需要，不必”，相当于don’t have to.
例： ---Must I finish the work today？
---Yes, you must. /No, you needn’t (don’t have to).
4、must和have to意思都是“必须”，常可以互换使用。但have to用于强调客观需要，意为“必须，不得不”；must用于表示主观意愿，意为“必须”。
例：①We’ll have to ask Zhang Hong instead. 我们必须去请张红代替了。
②We must work hard at school. 我们在学校必须努力学习。
【知识点6】need
need作情态动词时，一般用于否定句或疑问句，无形态变化。肯定回答常用must或have to;否定答语常用needn"t.
例：①You needn"t do it again．你不需要再做了。
②He needn"t worry about it．这件事他无需担心。
③Need he do this homework first？他需要先做这些作业吗？
【知识点7】shall/ had better
1、shall用于第一人称，表示征求意见、询问，用于第二、三人称时，表示警告、命令、允诺等。
2、had better意为“最好......”，后接动词原形，否定形式在后面直接加not，再接动词原形。
例：①Shall we start the meeting at once? 我们立即开会好吗？
②It’s late. You’d better go and look for him. 太迟了。你最好去找他。
③ You’d better not read books in poor light. 你最好不要在微弱的灯光下看书。
【知识点8】will和would
1、will用于第二人称表示询问、请求，也可以表达现在的“意愿”。
2、would用来表示过去的意愿或委婉的询问。
例：①Will you get me some chalk? 你拿些粉笔给我好吗？
②Would you like some bananas? 来点香蕉好吗？
【知识点9】should
⑴表义务。意为“应该”，用于各种人称。
You should be polite to your teachers.
You shouldn’t waste any time.
⑵表推测，意为“想必一定、照说应该、估计”等。The film should be very good as it is starring first-class actors.
They should be home by now.
【知识点10】ought to
⑴表义务，意为“应该”（因责任、义务等该做），口气比should稍重。
You are his father. You ought to take care of him.
You oughtn’t to smoke so much.
⑵表推测，暗含很大的可能，语气较弱。
Han Mei ought to know his telephone number.
There’s a fine sunset; it ought to be a fine day tomorrow.
当堂练习1：
一、用所给词的适当形式填空
1.Marcia said everyone should_________(keep) quiet in the dining room.
2.I must (finish) this before I go.
3.She shouldn’t _________(go) to the zoo now, she must __________(stay) at home.
4.My mother can’t __________(find) her glasses. They _________(be) in her bag just now.
5.I can __________(get) up early. I __________(do) morning exercise at six.
6.What can I (do) for you?
二、用适当的情态动词填空
1. Must I borrow the book with my ID card? No, you ________. (must，needn’t )
2. ________ I use your car? Yes, you can. ( May ,Would)
3. ________ I go home now? No, you _________stay here.(May, may ; May, must)
4. My mother is ill. I _________ stay at home and look after her.( must ;may)
5. ________ you like some tea?(Would,Can)
6.Must I borrow the book with my ID card? No, you ________. (needn’t, can’t)
7. ________ we play basketball this afternoon? (May ,Shall)
8.You ________ take more exercise. (shall, should)
9.The watch ________ tell us the time. (can, Must)
10.________ you tell me how to get to the Xuanwu Park? (Must, Can)
三、单项选择
（）1. you like some milk ?
A . Would B. Could C . Can D.Must
（）2. We pick the flower in the park.
A. mustn’t B. don"t C. couldn’t D. may not
( ) 3.We should more trees, and we shouldn’t cut any trees.
A. plant B. planting C. plants D.planted
( ) 4.Shall we visit the factory?---- .
A.Yes,we do. B.Yes, we shall. C.All right. D.Yes, we can
( )5.It is late. I go home now.
A. could B. would C. must D. will
( )6.What I do at the meeting?
A. has to B. would like C. should D. not should
( )7. you tell me where the Hualian Market is?
A. Could B. Must C. Should D. Have
( )8. --- you to have some pudding? —Yes, please.
A. Had. . . better B. Ought.../ C. Would…like D. Would…mind
( )9. You’d better you know when you don’t and it’s better for an electrician.
A. not to pretend... to send B. not pretend…send C.not to pretend…send D. not pretend…to send
( )10. —Shall I tell Michael about the news? —No, you . He’s already known it.
A. can’t B. mustn’t C. needn’t D. don’t
(二)动词不定式作宾语
1. 概述：
动词不定式是动词的非谓语形式之一，其表现形式为：to+动词原形。其中to是动词不定式符号，没有任何词义。其否定形式是在to前面加not。
2. 用法:
动词不定式没有人称和数的变化，它具有名词、形容词和副词的特征，同时也保留了动词的某些特征，在句中可充当主语、表语、宾语、宾语补足语、定语以及目的状语等。
(1)常见的能带动词不定式作宾语的动词有：want，like，love，wish，hope，need，try，ask，seem，help，learn，decide，plan，start，begin，forget，remember，choose ，prepare，agree等。
e.g: ① Kate wants to be a doctor when she grows up．
② He decided to buy a new MP4．
③ We all hope to go to Taizhou next month．
④ I don’t like to be late for school.
⑤I forgot to bring the MP4 hem.
（2）有些动词后面接复合宾语时，常用it作形式宾语，而真正的宾语则由动词不定式来担当，并位于宾语补足语之后。常见的这样的动词有find，think，feel，make等。
e.g: ① I find it interesting to play computer games我发现玩电脑游戏很有趣。
② We all think it very difficult to finish the work in an hour.
当堂练习2：用所给动词的适当形式填空
1. When I saw Jim on my way home, I stopped _______ (talk) with him.
2. I forgot_______ (tell) him about it and told him again.
3. You can ask that strong man_______ (help) you_______ (move) the big stone.
4. Who told you_______ (do) this?
5. Mary decided _______ (do) her homework as soon as she got home.
6. Do you plan_______ (take) Linda out for a walk after supper?
3.“疑问词+不定式”结构
疑问词who，what，which，when，where和how后接动词不定式可在句中作宾语、主语、表语。
e.g: ① I don’t know what to do next．
②Can you tell me how to get to the hospital?
【知识拓展】
(1)动词不定式作主语。
e.g: To help others is our duty．帮助他人是我们的责任。
【注意】不定式作主语时，在多数情况下，常用it作形式主语，而把不定式放在后面
To learn English well is very important for us
=It is very important for us to leam English well.
It is very difficult for me to work out the Maths problem.
(2)动词不定式作表语。
My wish is to be a basketball player．
My sister’s dream is to be a nurse．
(3)动词不定式作定语。
I have two new books to read．
Do you have anything to say for yourself?
(三) 在部分动词和形容词加后缀 –ing, -ness, -ion构成名词
shop-shopping happy- happiness decide-decision
invite-invitation discuss- discussion celebrate- celebration feel- feeling meet- meeting
sick- sickness dark- darkness kind- kindness begin- beginning collect-collection
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