题目内容：

_____were you there?only four days.填什么呢?
people show their love to their mothers ____giveing gifts on Mother'sDay A to B by C at Dfor选择什么呢?

优质解答

_How long____were you there?only four days
选B 通过某种方式(手段) 用介词by 后面接动词的ing 形式