I borrowed the book three weeks ago. 同义句转换 I _ _ the book since three weeks ago.

Question

I borrowed the book three weeks ago. 同义句转换 I _ _ the book since three weeks ago. 现在完成时since和for什么的弄不懂 have+v(pp) have什么时候用had

Answer 1

have
kept
现在完成时
的since
后加
点时间
for
加
段时间
比如：I
haven't
seen
you
since
we
graduated.
I
haven't
seen
you
for
5
years.
有一个过去时间，在描述在这个时间点之前发生的动作，用had
done
I
had
done
my
work
before
I
left
the
office.