在英语定语从句中，用“介词+关系代词”在从句里缺成分用还是不缺成分用？

Question

如题所述

Answer 1

介词＋关系代词＝关系副词，关系副词在从句中作状语，也就是说，没有他，从句的主谓（宾）是齐全的，不缺主要成分，可以参照moonlight给的例子

Answer 2

定语从句的所有的关系词在句子中都是充当句子成分的
介词+关系代词
分两种情况
一种是关系副词可以等同于介词+关系代词
例如：1.I
will
never
forget
the
day
when
I
met
him.
I
will
never
forget
the
day
on
which
I
met
him.
因为具体到某一天，所以when
可以用
on
which
来替换
2.
He
didn't
want
to
recall
the
year
when
his
girl
left.
He
didn't
want
to
recall
the
year
in
which
his
girl
left.
另一种是动词与介词的固定搭配。
例如：I
know
the
girl
to/with
whom
John
is
talking.
这句话中，talk
to/with
sb.是固定搭配。

Answer 3

介词+关系代词
在定从中充当句子成分。
This
is
the
company
where
(in
which
)I
used
to
work.
in
which
在定从中做状语，表示地点