爱华网Be动词用法。
be动词(am、is、are)+not、
情态动词can+ not、
助动词(do、does) + not
如何将一个肯定的陈述句改为否定句：
1、看句中有无be动词，如有，直接在be动词后+ not。
2、看句中有无情态动词，如有，直接在情态动词后+ not。
3、如上述二者都没有，就应用助动词+ not。分四个步骤：
(1)肯定陈述句中本来是没有助动词的，要加上去，位置在主语(某人或某物)后，动词前。
(2)确定助动词用do、does，根据句中动词，动词是原形的助动词就用do，动词是第三人称单数的助动词就用does，
(3)在助动词后加not。
(4)原句中动词假如发生变化就要恢复成原形。
强调一点，有some的要考虑是否要用any。
如何将一个肯定的陈述句改为一般疑问句：
1、看句中有无be动词，如有，把be动词提到句首即可。
2、看句中有无情态动词，如有，把情态动词提到句首即可。
3、如上述二者都没有，就应把助动提到句首。分四个步骤：
(1)肯定陈述句中本来是没有助动词的，要加上去，位置在主语(某人或某物)后，动词前。
(2)确定助动词用do还是does，根据句中动词，动词是原形的助动词就用do，动词是第三人称单数的助动词就用does
(3)把助动词后提到句首。
(4)原句中动词假如发生变化就要恢复成原形。
强调一点，有some的要考虑是否要用any。
表示将来将要发生的动作， 经常和tomorrow, next year, the day after tomorrow, the year after the next, in five hours' time, etc. 表示将来的词联用。
结构：主语+助动词will+动词原形
I will go to America tomorrow.
The pilot will fly to Japan the month after the next.
Jack will move into his new house tomorrow morning.
★变疑问句将助动词移到句首
Will you go to America tomorrow?
Will the pilot fly to Japan the month after the next?
Will Jack move into his new house tomorrow morning?
★变否定句在助动词后面加not
I will not go to America tomorrow.
The pilot will not fly to Japan the month after the next.
Jack will not move into his new house tomorrow morning.
★肯定回答及否定回答
Yes, I will. / No, I will not.
Yes, he/she will. / No, he/she will not.
Yes, he will. / No, he will not.
★特殊疑问句
What will you do?
表示现在正在进行的动作。
构成： 主语+be动词+动词的现在分词+其它成分
We are having lunch.
He is reading a book.
The dog is running after a cat.
The boys are swimming across the river.
★变疑问句将be动词移到句首
Are we having lunch?
Is he reading a book?
Is the dog running after a cat?
Are the boys swimming across the river?
★变否定句在be动词后面加 not
We are not having lunch.
He is not reading a book.
The dog is not running after a cat.
The boys are swimming across the river.
★特殊疑问句：what, which, how, where, who, etc.
疑问词+动词+主语+现在分词
What are you doing?
What is she doing?
What is the dog doing?
没有进行时的动词(必背)
表示状态，思想，感情和感觉的动词不能表示正在进行的动作
1. 表示感觉，感官的词
see, hear, like, love, want,
2. have, has当”拥有”讲时没有进行时
表示过去发生的动作或事件， 常和表示过去的时间状语连用，如yesterday, last night, the day before yesterday, 3 days ago,
含有be动词的句子， 将动词变为过去式，am, is的过去式为was，are的过去式为were
I was at the butcher’s.
You were a student a year ago.
The teacher was very beautiful ten years ago.
★变疑问句将be动词移动到句首
Were you at the butcher’s?
Were you a student a year ago?
Was the teacher very beautiful ten years ago?
★变否定句在be动词后面加not
I was not at the butcher’s.
You were not a student a year ago.
The teacher was not very beautiful ten years ago.
★肯定回答否定回答
Yes, I was. No, I was not.
Yes, you were. No, you were not.
Yes, he/she was. No, he/she was not.
★特殊疑问句：
What did you do?
(必背)
不含有be动词的句子，将动词变为过去式
I finished my homework yesterday.
The boy went to a restaurant.
The Sawyers lived at King Street a year ago.
★变疑问句在句首加did， 动词变为原型
Did you finish your homework yesterday?
Did the boy go to a restaurant?
Did the Sawyers live at King Street a year ago?
★变否定句在主语和动词之间加did not
I did not finish my homework yesterday.
The boy did not go to a restaurant.
The Sawyers did not live at King Street a year ago.
★肯定回答及否定回答
Yes, I did. No, I didn’t.
Yes, he did. No, he didn’t.
Yes, they did. No, they did not.
构成：主语+助动词have, has+过去分词
用法：
2) 表示过去发生的和现在有某种联系的动作，常和just, usually, already, since等时间副词连用
I have just had lunch. (饱了，不用再吃了)
He has had a cup of tea.(不渴了，不用再喝)
They have already had their holiday. (不能再度假了)
The boy has already read the book. (已经知道书的内容了，不用再看了)
3) 询问别人是否做过某事一般用现在完成时：
Have you finished your homework?
Have you been to Beijing?
Have he seen the film?
4) 表示开始于过去并持续到现在的动作
I have lived in Beijing for twenty years.
I have worked for this school for 1 year.
5) 表示一种经历，经验：去过…地方，做过…事情，经历过…事情
I have never had a bath.
I have never seen a film.
I have never been to cinema.
I have ever been to Paris.
Have been to表示去过，have gone to 表示去了
I have been to London.(人已经回来)
He has gone to London.(人还在那里)
6) 表示一种结果， 一般不和时间副词联用
I have lost my pen.
I have hurt myself.
He has become a teacher.
She has broken my heart.
句型变化：
★变疑问句将助动词移到句首，变否定句在助动词后面加not.
e.g. Have you lost your pen? I have not lost my pen.
★肯定回答及否定回答
Yes, I have. No, I have not.
★特殊疑问句：
What have you done?
What has he done?
一般过去时与现在完成时的区别：
凡是有明确的表示过去的时间状语的句子为过去时
注意：有些动词表示的动作有一个终点，不能再延续，因此不能和表示一段时间状语连用
错：I’ve left Beijing for 3 days.
对：I left Beijing 3 days ago. I have been away from being for 3 days.
用法：在过去的时间里，两个动作中，发生在前的那个动作要用过去完成时。
结构：had+过去分词
After she had finished her homework, she went shopping.
They had sold the car before I asked the price.
The train had left before I arrived at the station.
After/before引导的时间状语从句放在句首要在句子后面加逗号，如果放在主句后则不用加。
1.变疑问句将助动词移到句首
Had she finished her homework?
2. 变否定句在助动词后面加not
She hadn’t finished her homework.
3. 肯定回答及否定回答
Yes, she had. No, she hadn’t.
4.特殊疑问句：
What had she done?
