英语问题教材上有一句话：IwaswatchingTVwhenmy
上有一句话：I was watching TV when my mother came in. 可否改成I was watching TV while my mother was coming in. 或者I watched TV when my mother came in? 如果不能，那为什么，关于when连接的两个并列句的时态问题谁能讲下，谢～～
不能,用while和when时,加ing的是延续性动词,如watch等,而came不是延续性动词,所以不能这样说。