who is singing in the next room?_____must be Maria.空格应该填It还是She?
问题描述：
who is singing in the next room?_____must be Maria.空格应该填It还是She?
或者是this,there?最好有分析!
答
填上 It .英语中对未知身份的人表示猜测时通常用It表示.