按使用目的可分为陈述句、疑问句、祈使句和感叹句。
一 陈述句（Declarative Sentences）：说明一个事实或陈述一种看法。
Light travels faster than sound. 光比声速度快。 （说明事实）
The film is rather boring. 这部电影很乏味。
（说明看法）
这里我们侧重讲述否定句
（一）概念
否定句指否定陈述句的句子。
（二）相关知识点精讲
1.用not构成的否定句：主语+助动词/ be+not+…
例句：
He is not back yet.
It is not true.
We haven’t forgotten you.
You shouldn’t be so silly.
We haven’t been invited yet.
He won’t go, but they will.
Money could not buy happiness.
I like the salad, but I don’t like this soup.
He wants a girl friend, but he doesn’t want to get married.
You didn’t understand what I said, did you ?
You needn’t try to explain.
I didn’t use to like opera, but now I’m getting interested.
I usedn’t to like opera, but now I’m getting interested.
2.祈使句的否定句：Don’t+动词原形…。
例句：
Don’t worry. I’ll look after you.
Don’t believe a word he says.
Don’t be so rude.
3. 非谓语动词（不定式，分词，动名词）的否定式：把not放在to do; doing; 的前面。
It’s important not to worry.
He said he deeply regretted not being able to help.
Not knowing what to do, Shelly asked advice of her friend.
He reproached me for not having told it to him.
4. not与除谓语以外的其他句子成分连用：
Come early, but not before six.
It’s working, but not properly.
I believe he will succeed, though not without some difficulty.
not用在I hope; I believe; I’m afraid; I guess; I suppose; I expect之后，构成省略句。
—Will it snow today ?
—I hope not.
5. 用no构成否定句：no+名词（单，复数，不可数）相当于not+ a +名词/ not + any +名词
No machine would work for long if it were not properly lubricated.
The nations of Europe and America have found that no country can produce all its needs without trading.
Take that towel, I have no other.
I can walk no farther.
There is no knowing what will happen.
6. 某些否定副词或代词：seldom; never; hardly; rarely; little; few; none; nowhere; neither等在句中构成否定句：
I can seldom find time for reading.
Mirror tells only the facts, never the poetry.
The rumor came from nowhere.
None but fools have ever believed it.
7. 否定转移：当think; believe; suppose; imagine等动词引导否定意义的宾语从句时，把从句中的not提到主句这些动词前面，是主句变成否定句：
I don’t think she’s at home, but I’ll go and see.
I don’t imagine that he’ll enjoy it.
8. 否定式疑问句：
Doesn’t she understand ?
Haven’t you booked your holiday yet ?
部分否定：
注意部分否定的结构：
Not all…=All…not…
Not both…=Both…not…
Not every…=Every…not…
I don’t remember all the names.
All is not gold that glitters.
It is not found everywhere.
Not everyone likes this film.
9. 用否定形式表示肯定的意义：
注意这些句型：
cannot…too.. / cannot… more: 越…就越好；再…不过了。
You cannot be too careful.
A man can never have too many friends.
（三）巩固练习
1. —Such a sudden turn in the road is too difficult for the new driver, isn’t it ?
—_____. He’s dealt with all kinds of troublesome situations before.
A. No, it isn’t B. Yes, it isC. No, he isn’t D. Yes, he is
2. —Aren’t you feeling tired ?
—______, I am rather.
A. Yes B. No C. Not at all D. Never
3. —She isn’t a dancing teacher, is she ?
—______.
A. Yes, she isn’tB. No, she is
C. Yes, she wasn’tD. No, but she was.
4. —Will you go shopping with us this afternoon ?
—_____but I’ve got quite a lot of homework to do.
A. of courseB. I’d like toC. That’s all rightD. No, I won’t
5. —If our parents would listen more to us, they would understand us better.
—_____. They just expect us to listen.
A. I believe not B. No problem C. Good ideaD. I can’t agree more
6. —Did you enjoy the trip ?
—I’m afraid not. And _____.
A. my classmates can’t either.B. my classmates don’t too.
C. neither do my classmatesD. neither did my classmates
7. Try to retell the story in your own words. ______ afraid to make mistakes.
A. Not to be B. Don’t C. No beD. Don’t be
（四）答案
AADBD DD
二 疑问句（Interrogative Sentences）：提出问题。有以下四种：
a. 一般疑问句（General Questions）：
Can you finish the work in time?
你能按时完成工作吗？
b. 特殊疑问句（W Questions; H Questions）：
Where do you live? 你住那儿？
How do you know that? 你怎么知道那件事？
c. 选择疑问句（Alternative Questions）：
Do you want tea or coffee?
你是要茶还是要咖啡？
d. 反意疑问句（Tag-Questions）：
这里我们侧重讲解反意疑问句
1) 陈述部分的主语是I，疑问部分要用 aren't I.
I'm as tall as your sister，aren't I?
2) 陈述部分的谓语是wish，疑问部分要用may +主语。
I wish to have a word with you, may I?
3) 陈述部分用 no, nothing, nobody, never, few, seldom, hardly, rarely, little等否定含义的词时，疑问部分用肯定含义。
The Swede made no answer, did he / she?
Some plants never blown (开花), do they ?
4) 含有ought to 的反意疑问句，陈述部分是肯定的，疑问部分用shouldn't / oughtn't +主语。
He ought to know what to do, oughtn't he? / shouldn't he?
5) 陈述部分有have to +v. (had to + v.)，疑问部分常用don't +主语（didn't +主语）。
We have to get there at eight tomorrow, don't we?
6) 陈述部分的谓语是used to 时，疑问部分用didn't +主语或 usedn't +主语。
He used to take pictures there, didn't he? / usedn't he?
7) 陈述部分有had better + v. 疑问句部分用hadn't you?
You'd better read it by yourself, hadn't you?
8) 陈述部分有would rather +v.，疑问部分多用 wouldn't +主语。
He would rather read it ten times than recite it, wouldn't he?
9) 陈述部分有You'd like to +v. 疑问部分用wouldn't +主语。
You'd like to go with me, wouldn't you?
10) 陈述部分有must 的疑问句，疑问部分根据实际情况而定。
He must be a doctor, isn't he?
You must have studied English for three years, haven't you? / didn't you?
He must have finished it yesterday, didn't he?
11) 感叹句中，疑问部分用be +主语。
What colours, aren't they?
What a smell, isn't it?
12) 陈述部分由neither… nor, either… or 连接的并列主语时，疑问部分根据其实际逻辑意义而定。
Neither you nor I am engineer, are we?
13) 陈述部分主语是指示代词或不定代词everything, that, nothing, this, 疑问部分主语用it。
Everything is ready, isn't it?
14) 陈述部分为主语从句或并列复合句，疑问部分有三种情况：
a. 并列复合句疑问部分，谓语动词根据邻近从句的谓语而定。
Mr. Smith had been to Beijing for several times, he should have been in China now, shouldn't he?
b. 带有定语从句，宾语从句的主从复合句，疑问部分谓语根据主句的谓语而定：
He is not the man who gave us a talk, is he?
He said he wanted to visit Japan, didn't he?
c. 上述部分主句谓语是think, believe, expect, suppose, imagine等引导的定语从句，疑问部分与宾语从句相对应构成反意疑问句。
I don't think he is bright, is he?
We believe she can do it better, can't she?
15) 陈述部分主语是不定代词everybody, anyone, somebody, nobody, no one等，疑问部分常用复数they，有时也用单数he。
Everyone knows the answer, don't they? (does he?)
Nobody knows about it, do they? (does he?)
16) 带情态动词dare或need的反意疑问句，疑问部分常用 need (dare ) +主语。
We need not do it again, need we ?
He dare not say so, dare you?
当dare, need 为实义动词时，疑问部分用助动词do + 主语。