写作业的英文是 do the homework。其中，“do”是动词，表示“做”；“homework”是名词，表示“家庭作业”或“功课”。所以，当你想要表达“写作业”这个意思时，可以用这个短语。例如：

1. It's time to do my homework.

2. I need to do my homework before I can go out.

3. She is doing her homework right now.