i have cleaned the door twice(对画线部分提问 划线部分:twice)_____ ______ _____ you _______the door?
问题描述:
i have cleaned the door twice(对画线部分提问 划线部分:twice)
_____ ______ _____ you _______the door?
答
How often have ...cleaned.
前面如果是四个空(这个比较好)
How many times have ...cleaned