看到本站看到一个问题：https://www.cpsenglish.com/question/8101
其中有When doing homework, he often listens to music.这个句子
这里的when doing应该是等于when he does homework还是等于when he is doing homework?
期望老师解惑，谢谢！
我读这句话的时候语感是 when doing =when he isdoing. 假如表达when he does homework, 这样的情况不省略，表示的是一种长期的平时习惯。When/While doinghis homework, he .... 比较多见。