你怎么还不写作业英文可以表达为：

Why haven't you done your homework yet？

Why don't you do your homework？

Why didn't you finish your homework？

这些表达方式都可以用来询问或提醒某人完成作业。希望这些对你有所帮助!如果有更多具体情境或需要更详细的表达，请告诉我。