I have been collecting shell for5years可以改成 I have been collecting shell since 5yearsago吗?

分类: 作业答案 • 2021-11-12 22:39:08

问题描述：

I have been collecting shell for5years可以改成 I have been collecting shell since 5yearsago吗?
为什么?

答

可以.
for是时间长度.
since是时间点.