Do you know when he came here?Let me think.He here since he graduated.A.had come B.has been C.had been

问题描述:

Do you know when he came here?
Let me think.He here since he graduated.
A.had come B.has been C.had been

B 现在完成时 有SINCE且后面是动词的过去时

C. had been
过去完成时

当然选 B.
since 是现在完成时的标志.