an hour or two agothey have played piano for one or two hours 追问They started to play the piano_______ _________ _________究竟是哪个题？！they have played piano for one or two hours 怎么不同于原题？！They started to play the piano_______ _________ _________one or two hours ago三个空三空是没法表达“一两个小时以前”的如果是“two hours ago" 与原句有出入