我有点忙——我可以晚点给你回电话吗？

I'm kind of busy - can I ___call you ___back later?

如果你收到这条消息，请给我回电话，号码是5681275。

If you get this message, please ___call me ___back at 5681275.

他没接，所以我明天会再打过去。

He didn't answer, so I'll ___call ___back tomorrow.