初二英语语法

情态动词的用法

情态动词用法归纳

情态动词是一种本身有一定的词义,但要与不带to的普通动词的不定式一起使用,给谓语动词增添情态色彩,表示说话人对有关行为或事物的态度和看法,认为其可能、应该或必要等。
情态动词后面加动词原形。

情态动词有can (could), may (might), must, have to, shall (should, will (would), dare (dared), need (needed), ought to等。 情态动词无人称和数的变化;不能单独使用,必须与其后的动词原形构成谓语

一、 can, could

1) 表示能力(体力、知识、技能)。

Can you lift this heavy box?(体力)

Mary can speak three languages.(知识)

Can you skate?(技能)

此时可用be able to代替。Can只有一般现在时和一般过去式;而be able to则有更多的时态。

I’ll not be able to come this afternoon.

当表示“经过努力才得以做成功某事”时应用be able to,不能用Can。如:

He was able to go to the party yesterday evening in spite of the heavy rain.

2) 表示请求和允许。

-----Can I go now?

----- Yes, you can. / No, you can’t.

此时可与may互换。在疑问句中还可用could,

might代替,不是过去式,只是语气更委婉,不能用于肯定句和答语中。

---- Could I come to see you tomorrow?

---- Yes, you can. ( No, I’m afraid not. )

3) 表示客观可能性(客观原因形成的能力)。

They’ve changed the timetable, so we can go by bus instead.

This hall can hold 500 people at least.

4) 表示推测(惊讶、怀疑、不相信的态度),用于疑问句、否定句和感叹句中。

Can this be true?

This can’t be done by him.

How can this be true?

二、 may, might

1) 表示请求和允许。might比 may语气更委婉,而不是过去式。否定回答时可用can’t

或mustn’t,表示“不可以,禁止”。

----Might/ May I smoke in this room?

---- No, you mustn’t.

---- May/Might I take this book out of the room?

---- Yes, you can. (No, you can’t / mustn’t. )

用May I...?征徇对方许可时比较正式和客气,而用Can I...?在口语中更常见。

2)用于祈使句,表示祝愿。

May you succeed!

3) 表示推测、可能性(不用于疑问句)。

might不是过去式,它所表示的可能性比may小。

1.He may /might be very busy now.

2.Your mother may /might not know the truth.

三、 must, have to

1) 表示必须、必要。

You must come in time.

在回答引出的问句时,如果是否定的,不能用mustn’t(禁止,不准),而用needn’t, don’t have to(不必).

---- Must we hand in our exercise books today?

---- Yes, you must.

---- No, you don’t have to / you needn’t.

2) must是说话人的主观看法, 而have to则强调客观需要。Must只有一般现在时, have to 有更多的时态形式。

1. he play isn’t interesting, I really must go now.

2. I had to work when I was your age.

3) 表示推测、可能性(只用于肯定的陈述句)

1. You’re Tom’s good friend, so you must know what he likes best.

2. Your mother must be waiting for you now.

四、 dare, need

1) dare作情态动词用时, 常用于疑问句、否定句和条件从句中, 过去式形式为dared。

1. How dare you say I’m unfair?

2. He daren’t speak English before such a crowd, dare he?

3. If we dared not go there that day, we couldn’t get the beautiful flowers.

2) need 作情态动词用时, 常用于疑问句、否定句。在肯定句中一般用must, have to, ought to, should代替。

1.You needn’t come so early.

2. ---- Need I finish the work today?

---- Yes, you must. / No, you needn’t.

3) dare和 need作实义动词用时, 有人称、时态和数的变化。在肯定句中,dare后面常接带to的不定式。在疑问句和否定句中,dare后面可接带to或不带to的不定式。而need后面只能接带to的不定式。

1. I dare to swim across this river.

2. He doesn’t dare (to) answer.

3. He needs to finish his homework today.

五、 shall, should

1) shall 用于第一人称,征求对方的意见。

What shall we do this evening?

2) shall 用于第二、三人称,表示说话人给对方的命令、警告、允诺或威胁。

1. You shall fail if you don’t work hard.(警告)

2. He shall have the book when I finish it.(允诺)

3. He shall be punished.(威胁)

六、 will, would

1) 表示请求、建议等,would更委婉。

Will / Would you pass me the ball, please?

2) 表示意志、愿望和决心。

1. I will never do that again.

2. They asked him if he would go abroad.

3) would表示过去反复发生的动作或某种倾向。would表示过去习惯时比used to正式,且没有“现已无此习惯”的含义。

1. During the vacation, he would visit me every other day.

2. The wound would not heal.

4) 表示估计和猜想。

It would be about ten o’clock when she left home.

七、 should, ought to

1) should, ought to表示“应该”,ought to表示义务或责任,比should语气重。

1. I should help her because she is in trouble.

2. You ought to take care of the baby.

2) 表示劝告、建议和命令。should, ought to可通用,但在疑问句中常用should。

1. You should / ought to go to class right away.

2. Should I open the window?

3) 表示推测

should , ought to (客观推测), must(主观推测)。

1.He must be home by now. (断定他已到家)

2.He ought to/should be home by now.(不太肯定)

3. This is where the oil must be.(直爽)

4. This is where the oil ought to/should be.(含蓄)
温馨提示:答案为网友推荐,仅供参考
第1个回答  2012-12-24
初二英语语法总结
1) leave的用法
1.“leave+地点”表示“离开某地”。例如:
When did you leave Shanghai?
你什么时候离开上海的?
2.“leave for+地点”表示“动身去某地”。例如:
Next Friday, Alice is leaving for London.
下周五,爱丽斯要去伦敦了。
3.“leave+地点+for+地点”表示“离开某地去某地”。例如:
Why are you leaving Shanghai for Beijing?
你为什么要离开上海去北京?
2) 情态动词should“应该”学会使用
should作为情态动词用,常常表示意外、惊奇、不能理解等,有“竟会”的意思,例如:
How should I know? 我怎么知道?
Why should you be so late today? 你今天为什么来得这么晚?
should有时表示应当做或发生的事,例如:
We should help each other.我们应当互相帮助。
我们在使用时要注意以下几点:
1. 用于表示“应该”或“不应该”的概念。此时常指长辈教导或责备晚辈。例如:
You should be here with clean hands. 你应该把手洗干净了再来。
2. 用于提出意见劝导别人。例如:
You should go to the doctor if you feel ill. 如果你感觉不舒服,你最好去看医生。
3. 用于表示可能性。should的这一用法是考试中常常出现的考点之一。例如:
We should arrive by supper time. 我们在晚饭前就能到了。
She should be here any moment. 她随时都可能来。
3) What...? 与 Which...?
1. what 与 which 都是疑问代词,都可以指人或事物,但是what仅用来询问职业。如:
What is your father? 你父亲是干什么的?
该句相当于:
What does your father do?
What is your father's job?
Which 指代的是特定范围内的某一个人。如:
---Which is Peter? 哪个是皮特?
---The boy behind Mary. 玛丽背后的那个男孩。
2. What...?是泛指,所指的事物没有范围的限制;而 Which...?是特指,所指的事物有范围的限制。如:
What color do you like best? (所有颜色)
你最喜爱什么颜色?
Which color do you like best, blue, green or yellow? (有特定的范围)
你最喜爱哪一种颜色?
3. what 与 which 后都可以接单、复数名词和不可数名词。如:
Which pictures are from China?
哪些图片来自中国?
4) 频度副词的位置
1.常见的频度副词有以下这些:
always(总是,一直) usually(通常) often(常常,经常) sometimes(有时候) never(从不)
2.频度副词的位置:
a.放在连系动词、助动词或情态动词后面。如:
David is often arrives late for school. 大卫上学经常迟到。
b.放在行为动词前。如:
We usually go to school at 7:10 every day. 我们每天经常在7:10去上学。
c.有些频度副词可放在句首或句尾,用来表示强调。如:
Sometimes I walk home, sometime I rides a bike. 有时我步行回家,有时我骑自行车。
3.never放在句首时,主语、谓语动词要倒装。如:
Never have I been there.
5) every day 与 everyday
1. every day 作状语,译为“每一天”。如:
We go to school at 7:10 every day. 我们每天7:10去上学。
I decide to read English every day. 我决定每天读英语。
2. everyday 作定语,译为“日常的”。
She watches everyday English on TV after dinner. 她晚饭后在电视上看日常英语。
What's your everyday activity? 你的日常活动是什么?
6) 什么是助动词
1.协助主要动词构成谓语动词词组的词叫助动词(Auxiliary Verb)。被协助的动词称作主要动词(Main Verb)。
助动词自身没有词义,不可单独使用,例如:
He doesn't like English. 他不喜欢英语。
(doesn't是助动词,无词义;like是主要动词,有词义)
2.助动词协助主要动词完成以下功用,可以用来:
a. 表示时态,例如:
He is singing. 他在唱歌。
He has got married. 他已结婚。
b. 表示语态,例如:
He was sent to England. 他被派往英国。
c. 构成疑问句,例如:
Do you like college life? 你喜欢大学生活吗?
Did you study English before you came here?你来这儿之前学过英语吗?
d. 与否定副词not合用,构成否定句,例如:
I don't like him. 我不喜欢他。
e. 加强语气,例如:
Do come to the party tomorrow evening. 明天晚上一定来参加晚会。
He did know that. 他的确知道那件事。
3.最常用的助动词有:be, have, do, shall, will, should, would
7) forget doing/to do与remember doing/to do
1.forget to do 忘记要去做某事。 (未做)
forget doing 忘记做过某事。 (已做)
The light in the office is still on. He forgot to turn it off.
办公室的灯还在亮着,它忘记关了。(没有做关灯的动作)
He forgot turning the light off.
他忘记他已经关了灯了。 ( 已做过关灯的动作)
Don't forget to come tomorrow.
别忘了明天来。 (to come动作未做)
典型例题
---- The light in the office is still on.
---- Oh,I forgot___.
A. turning it off B. turn it off
C. to turn it off D. having turned it off
答案:C。由the light is still on 可知灯亮着,即关灯的动作没有发生,因此用forget to do sth.而forget doing sth 表示灯已经关上了,而自己忘记了这一事实。此处不符合题意。
2.remember to do 记得去做某事 (未做)
remember doing 记得做过某事 (已做)
Remember to go to the post office after school. 记着放学后去趟邮局。
Don't you remember seeing the man before? 你不记得以前见过那个人吗?
8) It's for sb.和 It's of sb.
1.for sb. 常用于表示事物的特征特点,表示客观形式的形容词,如easy, hard, difficult, interesting, impossible等:
It's very hard for him to study two languages. 对他来说学两门外语是很难的。
2.of sb 的句型一般用表示人物的性格,品德,表示主观感情或态度的形容词,如good, kind, nice, clever, foolish, right。
It's very nice of you to help me. 你来帮助我,你真是太好了。
3.for 与of 的辨别方法:
用介词后面的代词作主语,用介词前边的形容词作表语,造个句子。如果道理上通顺用of,不通则用for。如:
You are nice. (通顺,所以应用of)。
He is hard. (人是困难的,不通,因此应用for。)
9) 对两个句子的提问
新目标英语在命题中有将对句子划线提问这一题型取消的趋势,现在采取的作法是对一个句子进行自由提问。例如:
句子:The boy in blue has three pens.
提问:1.Who has three pens?
2.Which boy has three pens?
3.What does the boy in blue have?
4.How many pens does the boy in blue have?
很显然,学生多了更多的回答角度,也体现了考试的灵活性。再如:
句子:He usually goes to the park with his friends at 8:00 on Sunday.
提问:1.Who usually goes to the park with his friends at 8:00 on Sunday?
2.Where does he usually go with his friends at 8:00 on Sunday?
3.What does he usually do with his friends at 8:00 on Sunday?
4.With whom does he usually go to the park at 8:00 on Sunday?
5.What time does he usually go to the park with his friends on Sunday?
6.When does he usually go to the park with his friends?
10) so、such与不定冠词的使用
1.so与不定冠词a、an连用,结构为“so+形容词+a/an+名词”。如:
He is so funny a boy.
Jim has so big a house.
2.such与不定冠词a、an连用,结构为“such+a/an+形容词+名词”。如:
It is such a nice day.
That was such an interesting story.
11) 使用-ing分词的几种情况
1.在进行时态中。如:
He is watching TV in the room.
They were dancing at nine o'clock last night.
2.在there be结构中。如:
There is a boy swimming in the river.
3.在have fun/problems结构中。如:
We have fun learning English this term.
They had problems getting to the top of the mountain.
4.在介词后面。如:
Thanks for helping me.
Are you good at playing basketball.

参考资料:别人的

第2个回答  2012-10-24
一. needn’t / don’t have to表“不必”
【疑难点津】mustn’t表示“禁止(做某事); 没有“不必”的意思。表示“不必”时,不能用mustn’t,而要用needn’t或don’t have to。所以当否定回答must(必须)问句时,要用needn’t或don’t have to。如:
— Must I finish the homework this evening?我必须今天晚上完成作业吗?
— No,you needn’t/don’t have to. 不必。
Jim, you mustn’t go out with Tony today. 吉姆, 今天你不许和托尼出去。
【高考链接】
1. You buy a gift, but you can if you want to. (2010湖南卷)
A. must B. mustn’t C. have to D. don’t have to
2. You park here! It’s an emergency exit. (2010重庆卷)
A. wouldn’t B. needn’t C. couldn’t D. mustn’t
【温馨提示】 “needn’t have +过去分词”表示“过去本来不必做某事,而实际上却做了”,属虚拟语气用法。如:
You needn’t have said so much to them. 你本来不必跟他们说那么多。
【高考链接】
3. Mark have hurried. After driving at top speed, he arrived half an hour early.
(2010天津卷)
A. needn’t B. wouldn’t C. mustn’t D. couldn’t
二. shall/will/would/can/could/may/might表“请求”
【疑难点津】上述情态动词均可用肯定或否定的问句形式表示“请求”或“征求意见”,但要特别注意与人称的搭配:shall用于第一、第三人称;will/would 用于第二人称;can/could/may/ might可用于各种人称。用would/could/might语气委婉,不表示“过去”时态。如:
Shall he open the window?要他打开窗户吗?
Would/Will you come and see me next Sunday?你下周来看我好吗?
【高考链接】
4. — I take the book out?
— I’m afraid not. (2010四川卷)
A. Will B. May C. Must D. Need
【温馨提示】 在陈述句中,shall用于第二人称、第三人称可表示说话者给对方的“允诺、命令、警告或威胁”。如:
You shall fail if you don’t work harder.(警告)
He shall have the book when you finish reading it. (允诺)
【高考链接】
5. — I haven’t got the reference book yet, but I’ll have a test on the subject next month.
— Don’t worry. You have it by Friday. (2010江苏卷)
A. could B. shall C. must D. may
三. should/ought to表“应该”
【疑难点津】含义有二:一是表示“有义务应该做某事”,常通用。细微区别是:用ought to多表示“因职责、义务或要求应该做正确的或好的事情”;而用should则含有“怎样做才是恰当的”。」二是表“判断”,意为“理应
(怎么样)。两者可用于虚拟语气结构“should/ought to have done”中,均表示“过去本来应该做某事,而实际上没有做”,用否定式则意思相反。如:
We should not use too many big words in our everyday speech. 在日常会话中我们不宜用太多的大词。(怎样做恰当)
We ought to stop the waste from polluting our environment.我们应该想办法不让垃圾污染环境。(职责)
They should wait for us at the theatre. 他们理应在剧院等我们。
You ought to have said sorry to her at that time. 你当时就应该向她道歉。
【高考链接】
6. I have watched that movie—it’ll give me horrible dreams. (2010山东卷)
A. shouldn’t B. needn’t
C. couldn’t D. mustn’t
四. can/could表示“能”
【疑难点津】含义有:1. 能够做某事(具备某种能力);2. 可能(客观可能性);3. 可以做某事(允许);4. 可能(推测)。如:
He is so strong that he can carry this heavy box upstairs.他如此强壮以致于能把这个重箱子搬上楼。(能力)
It can be quite cold here at night. 这儿的晚上可能会非常寒冷。(可能性)
You can use my bike at any time. 你随时能用我的单车。(允许)
Mary can be in the office. 玛利可能在办公室。(推测)
【高考链接】
7. If it were not for the fact that she sing, I would invite her to the party. (2006福建卷)
A. couldn’t B. shouldn’t C. can’t D. might not
8. I’m afraid Mr. Harding see you now. He’s busy. (2010全国II)
A. can’t B. mustn’t C. shouldn’t D. needn’t
【温馨提示】can/could用于否定句、疑问句或感叹句中可表示“惊异、怀疑、不相信”等态度,can和could可以互换,没有时态区别,用could的语气比can缓和。如:
Where can/could they be now?他们现在能在哪儿呢?
How could he be so careless! 他怎么能这么粗心!
第3个回答  2009-04-10
should shouldn't can can't may mayn't 这些都是情态动词,还有一点短语类的,记不清了。
用法么,就是不管主语是三单还是非三单,都用原型,没有过去式和三单形式,后面跟动词也一般用原型,所以应该是在一般现在时里用,或者说,没有什么特定的时态吧。
很不专业哦,也许是错的,回去我查查书再来告诉你吧。
第4个回答  2009-04-11
+动词原型
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