（一）句子種類概述
句子按種類可分為陳述句、疑問句、祈使句和感嘆句。

（二）基礎(chǔ)知識(shí)梳理
1．陳述句
陳述句用來說明事實(shí)或表示說話人的看法。
1)陳述句的肯定形式。如：
We are students.
We must obey the traffic rules.
We clean the room every day.

2)陳述句的否定形式
把陳述句改為否定句可以歸納為以下三種情況：
(1)在be，have，will，shall（包括情態(tài)動(dòng)詞）后直接加not。如：
We aren't students．
You needn't hand in your homework today.
(2)在助動(dòng)詞do，does，或did后加not，再把它們放在行為動(dòng)詞前面，而行為動(dòng)詞用原形。如：
We don't clean the room every day.
(3)否定句可由其他形式表示。如句中出現(xiàn)no，nobody，few，little，neither，hardly，nor，never等。如：
There are no books on the desk.
I can hardly answer your question.
Neither of the twins is a doctor.

2．疑問句
疑問句就是提出問題，讓對(duì)方作出回答。英語中有四種疑問句，即一般疑問句、特殊疑問句、選擇疑問句、反意疑問句。
1)一般疑問句
用于詢問一個(gè)事實(shí)是否屬實(shí)，其回答通常是Yes或No。其結(jié)構(gòu)為：
be，will，have，助動(dòng)詞+主語+（主動(dòng)詞）/賓語
如：Is she a university teacher?
Will it be windy tomorrow?
Did he take part in the maths contest yesterday?

2)特殊疑問句
特殊疑問句對(duì)句中某一特定部分提問，以特殊疑問詞開頭根據(jù)實(shí)際情況，不必用Yes或No回答。常見的特殊疑問詞有what，who，whom，when，what，time，where，why，which，whose，how old，how many+可數(shù)名詞復(fù)數(shù)，how much+不可數(shù)名詞，how long，how far，how fast，how soon等。其結(jié)構(gòu)為：
疑問句+一般疑問句語句
如：Who has lunch fastest at school in our class?
What are you doing now?
How long have you lived here?

3)選擇疑問句
選擇疑問句通常提供兩種或兩種以上情況，詢問對(duì)方選擇哪一種?；卮饡r(shí)選擇一種，不必用Yes或No。
一般疑問句+A or B
如：Is there any coffee or water in the cup?
Do you often play basketball or play the piano?
特殊疑問句，A or B？ 或A，B or C？
如：Which is the biggest, the moon, the earth or the sun?
Which do you like better, the record or the ball?
4)反意疑問句
由兩部分組成，前半句為陳述句，后半句是一個(gè)附著在前半句上的簡(jiǎn)短問句，回答時(shí)用Yes或No。它的構(gòu)成和回答主要如下：
(1)肯定陳述句+否定附加疑問部分？
如：They are interested in collecting stamps, aren't they?
一Yes，they are. 是的，他們對(duì)集郵感興趣的。
一No，they aren't. 不，他們對(duì)集郵不感興趣的。
(2)否定陳述句+肯定附加疑問部分？
如：Tom didn't pass the exam, did he?
一Yes，he did. 不，他通過考試。
一No，he didn't. 9是，他沒通過。

3．祈使句
祈使句表示請(qǐng)求、命令、叮囑、邀請(qǐng)、勸告等。
1)祈使句的肯定結(jié)構(gòu)
如：Come in，please.
Let me have a try.
Let's go to the cinema together.
2)祈使句的否定結(jié)構(gòu)是在動(dòng)詞前面加上don't，
如： Don't be late for school.
Don't walk on the grass.

4．感嘆句
1) 感嘆句表達(dá)說話人說話時(shí)的驚異、喜悅、氣憤等情緒。它常由what或how開頭或引導(dǎo)。
感嘆詞What+強(qiáng)調(diào)部分（名詞）+主語+動(dòng)詞謂語
如：What a mess picture it is!
What an exciting film we saw yesterday!
2) 感嘆詞How+強(qiáng)調(diào)部分（形容詞或副詞）+主語+動(dòng)詞謂語
如：How wonderful the film is!
?