Noun ならいざ知らず JLPT N1 Very formal / literary

~nara izashirazu

Expresses 'maybe X is possible, but Y is definitely not'. Often 'let alone...'.

Formal, literary "X is one thing, but Y is another (less certain) matter".

Formation

Noun1 + ならいざ知らず + Noun2 (comment)

Explanation

「Xならいざ知らず、Yは…」 emphasizes that while X might be possible or acceptable, Y is out of the question or even more difficult. It can be translated as 'I could understand X, but Y is impossible' or 'Maybe X, but definitely not Y.'

Example sentences

数学ならいざ知らず、物理なんて全然わからない。

Math might be manageable, but as for physics, I'm completely clueless.

Suugaku nara iza shirazu, butsuri nante zenzen wakaranai.
5キロならいざ知らず、10キロなんて走れません。

Maybe I could run 5 kilometers, but 10 kilometers is out of the question.

Go kiro nara iza shirazu, juu kiro nante hashiremasen.
日本語ならいざ知らず、中国語なんて話せない。

I might be able to speak Japanese, but Chinese is impossible for me.

Nihongo nara iza shirazu, chuugokugo nante hanasenai.
冷たい水ならいざ知らず、熱い水で泳ぐなんて考えたこともない。

Maybe cold water, but swimming in hot water never even crossed my mind.

Tsumetai mizu nara iza shirazu, atsui mizu de oyogu nante kangaeta koto mo nai.