Question

By no means      true that all native speakers of English know their own language very well．

A．is that

B．that is

C．is it

D．it is

Answer 1

C

考查倒装句。By no means 意为绝不，否定词放句首时，要用部分倒装，排除BD.根据句子结构可知，该句为主语从句，it 作形式主语。
句意为每个以英语为母语的人都很好地了解他们都语言，这绝不是真的。