he will go out to play for a while when（完成） all his homework 括号里的英文是什么

题目

he will go out to play for a while when（完成） all his homework 括号里的英文是什么

答案

填 To finish.
When 后要以接不定式,但不可以接现在分词.
例：
Ask him when to open it.
问问他什么时候打开
They knew when to attack and when to retreat.
他们知道什么时候进攻和什么时候撤退.