While doing homework, he often listens to music simultaneously.
While doing homework, he often listens to music.
While doing homework, he often listens to music at the same time.
While doing homework, he is often listening to music.
以上都可以。
楼上三位都有语法错误,帮他们改一下:
1. He often does his homework while listening to music.
2. He is often doing his homework while listening to music.
3. He often does homework while listening to music.
参考资料:在美国上学