不得而知 bù dé ér zhī

ㄅㄨˋ ㄉㄜˊ ㄦˊ ㄓ

HSK 7-9core 10k

1unknown

2unable to find out

zhè这gè个jì huà计划néng fǒu能否chéng gōng成功hái还bù dé ér zhī不得而知。

这个计划能否成功还不得而知。

It is yet to be seen whether this plan will succeed or not.

当然，那些热水瓶是不是他们自己的就不得而知了。

Obviously, we don't know if those thermos flasks are their own.