来源:学生作业帮 编辑:神马作文网作业帮 分类:英语作业 时间:2024/10/02 14:27:45
主语+[ ]+动词ing
主语+[ am/ is /a re ]+动词ing
构成现在进行时
如:What are you doing
I am listening to the radio.
主语+[ was / were ]+动词ing
构成过去进行时
如:I was doing my homework when my mother arrived home yesterday.
不明白的再问哟,请及时采纳,多谢!