我不知道他何时会回来。

I don't know when he will come back.

youdao

你认为他何时会回来？

When do you expect him back?

youdao

约翰没有说何时会回来，但我推测他将回来吃晚饭。

John did not say when he would return, but I presume he 'll be back for dinner.

youdao

约翰没有说何时会回来，但我推测他将回来吃晚饭。

John did not say when he would return, but I presume he 'll be back for dinner.

youdao