Question

关于It is /has been +时间 since +过去时 表达两种意思的问题

Answer 1

It
is
/has
been
+时间
since
+过去时
两种用法其实是一样的，用is陈述情况，用has
been
强调从。。。起到现在的时间长度
It
is
three
years
since
I
began
to
learn
English.=It
has
been
three
years
since
I
began
to
learn
English

Answer 2

1.it
is
some
time(一段时间)
+
since引导的时间状语从句
=
it
has
been
some
time(一段时间)
+
since引导的时间状语从句
该固定句型意思是“自从...以来已经多久时间了”.