call in和call on的区别

call
on：＝call
upon
sb/sth，意思是短暂访问或拜访某人；
call
in：（尤指向工作单位）打电话汇报；
call
sb
in：请……来帮忙
call
off：通常应表示为call
sb/sth
off。意思是叫（人或狗）走开（以停止攻击）或取消、撤销（计划的活动）
我只能帮你到这了，到句子里你自己理解吧

call
in
1.叫(某人)进来;
来访
Call
in
this
evening
if
possible.
可能的话今晚来一趟。
Please
call
Kehr
in.
请凯尔进来。
2.找〔请〕来
How
many
friends
will
you
call
in?
你将邀请多少位朋友?
A
lawyer
is
often
called
in
to
write
a
will.
律师常被请来写遗嘱。
3.用电话通知;
打电话来（工作单位等）
The
director
has
just
called
in
to
say
that
she'll
be
late.
主任来电话说她要迟些时候来。
All
the
reporters
rushed
to
the
telephone
to
call
in
their
stories
when
the
game
was
over.
比赛结束时,
所有的记者都冲到电话机房,
用电话把采访的情况传递出去。
call
on1.拜访(某人)
He
often
calls
on
me.
他常常来拜访我。
2.叫,
号召
The
government
called
on
the
workers
to
oppose
waste.
政府号召工人反对浪费。
3.要求,
请求
He
called
on
his
friends
to
help
him.
他向朋友求助。