When did you first start____the piano?A.playing B.play C.plays D.to playing选哪个?为什么呢
问题描述：
When did you first start____the piano?A.playing B.play C.plays D.to playing选哪个?为什么呢
答
A.
start to do或者start doing.
而piano是乐器,所以必须是play the piano
所以应该选择第一个A