Not knowing each other?

彼此不了解？

youdao

They said goodbye to each other, not knowing that they were never to meet again.

他们互相到别，但是不知道他们这是永别。

youdao

They said goodbye to each other, not knowing that they were never to meet again.

他们互相到别，但是不知道他们这是永别。

youdao