I ()my homework,I guess I can't join you.

问题描述:

I ()my homework,I guess I can't join you.
A.don't finish
B.didn't finish
C.haven't finished
D.won't finish
答案是选C,可我选的A,为什么?

因为现在完成时表示过去发生,对现在有影响
没完成作业的影响是不能加入你们