同义句转换 Why did they set up the stage in the hall?------ ------ the stage set up for in the hal

题目

同义句转换 Why did they set up the stage in the hall?------ ------ the stage set up for in the hal
答案为什么是What was?

答案

why= what forfor 表示原因比如 the stage was set up for a concert the hall 大厅里的舞台是为了一场音乐会而被搭建的对concert 提问就是 what was the stage set up for in the hall 就等于 why did they set ...