Question

(that)you don't like him is none of my business为什么不是whether what who

Answer 1

用that,句意是
你不喜欢他，这不关我事。
that
you
don't
like
him
is
none
of
my
business
.句中is是谓语，整个句子是主语从句。从句中you
don't
like
him
表达完整，内容结构都不缺，而主语从句不可省略引导词，于是我们用毫无意义的that来引导该从句。whether
在从句中，有“是否”的意思，此时便不合要求。
要用whether，则句子改成：
whether
you
like
him
or
not
is
none
of
my
business.
你是否喜欢他，这不关我事。