改为一般疑问句：The meeting has been on for fifteen minutes.

改为一般疑问句：The meeting has been on for fifteen minutes.
The meeting has been on for fifteen minutes.改为一般疑问句.
_ the meeting _ _ for fifteen minutes?
_代表一条横线,这是人教版（仁爱英语）九年级上册练习册的一题.
拜托把解题思路也写出来,