Simone
对比学习，掌握does do did 的用法并不难
以下面三个句子为例：
a) He studies English. 他学习英语。
b) They look young. 他们看来挺年轻。
c) We went to school yesterday. 我们昨天上学了。
1、上述三句在强调谓语的时候，does ,do ,did请强调作用：
a) He does study English. 他的确学习英语。
b) They do look young. 他们的确看来挺年轻。
c) We did go to school yesterday. 我们昨天的确上学了。
2、在构成否定句和疑问句的时候does ,do ,did作助动词
a) He doesn't study English. Does he study English?
b) They don't look young. Do they look young?
c) We didn't go to school yesterday. Did you go to school yesterday?
3、does do did也可以作为一般动词，意为“做、进行”。
a) He does his homework in the evening.
b) I do shopping on Sundays.
c) He did his best yesterday.
