不得而知

不得 buˋ deˊ

(Am not, Are not allowed, Cannot, Is not, Must, Not be, Was not, Were not) Cannot, Must not, To not be allowed, Am not allowed, Are not allowed, Is not allowed, Was not allowed, Were not allowed

而 erˊ

But, And so, And, Yet, Then, Otherwise, In this case

知 zhi ˉ

Know, Perceive, Realize, Comprehend, Be Aware