When did you start to play the piano A.For two years B.Since two _其他解答

When did you start to play the piano A.For two years B.Since two years ago C.Since I was ten
D.When I was ten,请说明理由,

人气：138 ℃　时间：2020-01-26 03:06:37

解答

ABC都是表示的时间段,要用how long提问
when提问的话,问的是时间点