Be動詞用法
be動詞（am、is、are）+not、
情態(tài)動詞can+ not、
助動詞（do、does） + not
如何將一個肯定的陳述句改為否定句：
1、看句中有無be動詞，如有，直接在be動詞后+ not。
2、看句中有無情態(tài)動詞，如有，直接在情態(tài)動詞后+ not。
3、如上述二者都沒有，就應(yīng)用助動詞+ not。分四個步驟：
�。�1）肯定陳述句中本來是沒有助動詞的，要加上去，位置在主語（某人或某物）后，動詞前。
（2）確定助動詞用do、does，根據(jù)句中動詞，動詞是原形的助動詞就用do，動詞是第三人稱單數(shù)的助動詞就用does，
�。�3）在助動詞后加not。
�。�4）原句中動詞假如發(fā)生變化就要恢復(fù)成原形。
強調(diào)一點，有some的要考慮是否要用any。
一般疑問句
一般疑問句
如何將一個肯定的陳述句改為一般疑問句：
1、看句中有無be動詞，如有，把be動詞提到句首即可。
2、看句中有無情態(tài)動詞，如有，把情態(tài)動詞提到句首即可。
3、如上述二者都沒有，就應(yīng)把助動提到句首。分四個步驟：
�。�1）肯定陳述句中本來是沒有助動詞的，要加上去，位置在主語（某人或某物）后，動詞前。
（2）確定助動詞用do還是does，根據(jù)句中動詞，動詞是原形的助動詞就用do，動詞是第三人稱單數(shù)的助動詞就用does
�。�3）把助動詞后提到句首。
�。�4）原句中動詞假如發(fā)生變化就要恢復(fù)成原形。
強調(diào)一點，有some的要考慮是否要用any。
過去式
表示過去發(fā)生的動作或事件， 常和表示過去的時間狀語連用，如yesterday, last night, the day before yesterday, 3 days ago,
含有be動詞的句子， 將動詞變?yōu)檫^去式，am, is的過去式為was，are的過去式為were
I was at the butcher’s.
You were a student a year ago.
The teacher was very beautiful ten years ago.
★變疑問句將be動詞移動到句首
Were you at the butcher’s?
Were you a student a year ago?
Was the teacher very beautiful ten years ago?
★變否定句在be動詞后面加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.
★特殊疑問句：
What did you do?
(必背)
不含有be動詞的句子，將動詞變?yōu)檫^去式
I finished my homework yesterday.
The boy went to a restaurant.
The Sawyers lived at King Street a year ago.
★變疑問句在句首加did， 動詞變?yōu)樵?/p>
Did you finish your homework yesterday?
Did the boy go to a restaurant?
Did the Sawyers live at King Street a year ago?
★變否定句在主語和動詞之間加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.
