____he studied in the university,he has made much progress inthe study of English.

分类: 作业答案 • 2022-01-09 18:04:33

问题描述：

____he studied in the university,he has made much progress inthe study of English.
A.WhileB.WhenC.SinceD.After

答

C
因为主句是现在完成时,而since是现在完成时的标志