文档介绍：英语基本句型
陈述句改否定句
陈述句变否定句的规则如下:
(1) 句中有be动词的,直接在be动词后面加not.
She is my sister.
She is not my sister.
(2) 句中有情态动词的,直接在情态动词后面加not
You e here tomorrow .
You may e here tomorrow.
(3) 句中谓语动词是实意动词,没有be动词am is are,也没有情态动词can may must的,在实意动词前面加don’t或doesn’t,,当主语是第三人称单数时,加doesn’。
She studies English at school .
She does not study English at school.
陈述句改疑问句
陈述句变疑问句的规则如下:
(1) 句中有be动词的,把be动词提到句首。
He is a writer.       
Is he a writer?
(2) 句中有情态动词的,把情态动词提到句首。
(must, may, can,could,need,…)
I can clean the window.
Can you clean the window?
(3)句中谓语动词是实意动词,没有be动词am is are,也没有情态动词can may must的,在句首前面加do或does,当主语是第三人称单数时,
He likes cows.  
Does he like cows?
肯定回答和否定回答
Are you boys?    
Yes,we are(No,we aren't)
Is she a nurse?  
Yes,she is.(No,she isn't)
Does he like cows?
Yes,he does.(No,he doesn't)
Do we dance after school? 
Yes ,we do.(No,we don't)
He is my brother.
He is not my brother.
=He isn’t my brother.
Is he my brother?
Yes,he is.
No,he is not.
= No,he isn’t