David has been a student here__one and a half years ago.a.for b.s_英语解答

David has been a student here__one and a half years ago.a.for b.since c.ago d.after

人气：218 ℃　时间：2020-02-05 05:45:16

解答

B
since表示从过去某一时间点到“现在”的“一段时间”.