if
引导的就是条件状语从句,而且你也完全可以根据汉语翻译来辨别。
(we
will
go
to
the
zoo【if
it
doesn't
rain
tomorrow.】(主句)【从句】
i
don't
know
if
it
will
rain
tomorrow.【这是一个if引导的宾语从句:我不知道明天是否会下雨。】
紧跟在if后,被if引导的那个句子是从句。含有主语的句子是主句。
e.g.
He
will
go
hiking
if
it
doesn't
rain
tomorrow.
从句:it
doesn't
rain
tomorrow.
主句:He
will
go
hiking.
e.g.
2
If
I
were
you,
I
would
have
stopped
him
directly.
从句:I
were
you
主句:I
would
have
stopped
him
directly.