since能不能与ago 连用，与for有什么区别。since具体有什么用法？

Question

如题所述

Answer 1

since的用法：译作“自从…以来”
(1)接时间点：如
I
have
stayed
in
that
country
since
1995.
要求：谓v.用现在完成时，而且须是延续性动词。
(2)接一段时间
+
ago：如
They
have
lived
in
that
house
since
two
years
ago.
要求：谓v.用现在完成时，而且须是延续性动词。
(3)接时间状语从句：如
I
have
loved
her
since
I
met
her
last
time.
/
Lily
has
stayed
at
home
since
she
left
school.
要求：主句的谓v.用现在完成时，而且须是延续性动词；从句的谓v.用一般过去时，而且须是终止性动词。
(4)用于句型“It’s
/
It
has
been
+
一段时间
+
since
+
时间状语从句”中，译作“自从…以来,
已经…(时间)了”。如
It’s
/
has
been
three
months
since
he
moved
to
this
city.
要求：主句的谓v.用一般现在时或现在完成时；从句的谓v.用一般过去时，而且须是终止性动词。
(5)用于句型“一段时间
+
has
passed
since
+
时间状语从句”中，译作“自从…以来,
…
(时间)已经过去了”。如上个例句还可写成：Three
months
has
passed
since
he
moved
to
this
city.
要求：主句的谓v.用现在完成时，而且动词必须是has
passed；从句的谓v.用一般过去时，而且须是终止性动词。
(6)注：当since用于否定句时，主句的谓v.可以是终止性动词。如
He
hasn’t
seen
the
film
since
last
month.
(7)相关词组：“从那时起”：ever
since、since
then、from
then
on.
注：ever
since作为一个词组，放句尾可单独使用。如I
have
given
up
smoking
ever
since.
另外，还可在since后接句子。since前加ever，只是加重语气而已。如
I
have
given
up
smoking
ever
since
I
caught
a
bad
cough.
(8)
since还可引导原因状语从句，译作“由于；因为”，相当于because。如
Since
he
was
lazy,
he
didn’t
finish
his
homework.

Answer 2

当然可以，这是现在完成时的时间状语之一，
比如：
he
has
been
a
teacher
since
2
years
ago
两年前，他就成为老师了（现在还是老师）