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.