They exercise two hours a day.(对划线部分提问) _______ ________ do they exercise a day?划线部分是 two hours

问题描述:

They exercise two hours a day.(对划线部分提问) _______ ________ do they exercise a day?
划线部分是 two hours

How long他们每天锻炼多长时间

How long~
意思就是他们每天运动多久/多长时间~