i'm seeing tne professor tomorrow,__he will be back from new yorkwhen who which that

i'm seeing tne professor tomorrow,__he will be back from new york
when
who
which
that

when

when
是定语从句。

when是为了形容前面的tomorrow,那是时间所以用when

whic.非限制性定语从句，因为有逗号所以不能选择when。which但先行词是tomorrow

tomorrow的时间状语从句，用when

when或者while都可以，但选项里只有when...

选when