At what time would you like us to call you tomorrow morning? 您想让我们明天早上什么时候叫醒您?

I need to make sure I'm waken up by 5:00. 我一定得在5点前被叫醒。

At what time do you want me to call you up, sir? 您要我什么时候叫醒您?

At 6 sharp tomorrow morning, please. 请在明早6点整叫醒我。

What time would you like the call? 您希望我们几点叫您?

Call me at 7:00 a.m. 早上7点钟叫我。