Tell him to call back later.

告诉他过一会儿回电话。

He asked you to call back.

他叫你给他回电话。

Would you like to call back later?

你过一会儿再打来好吗？

When would you like me to call back?

你想我什么时候回电话给你？

This is Tom. Could you tell him to call back?

我是汤姆，可以叫他打给我吗？