You can see who is calling through caller ID.

你可以通过来电显示看到谁在打电话。

I like using caller ID to identify who is calling.

我喜欢使用来电显示来识别谁在打电话。

May I ask who is calling?

请问你贵姓?

Can I ask who is calling?

请问您是哪位?

May I know who is calling?

我能知道您是哪位吗？

This is Doris. Who is calling please?

我是多丽丝。请问您是哪位啊？

May (Can) I ask who is calling, please?

请问是谁打来的？

Who is calling me up at this unearthly hour?

谁在这个荒唐的时刻打电话给我？

Could (Can, May) I tell him who is calling?

我能告诉他是谁打来的吗？

This is Frank speaking. May I ask who is calling?

我是弗兰克。请问您是哪位？