The following are for your reference:
Who is the person over there?
What time is it?
Will she buy it?
Mike said, "Did you see Tom yesterday?"
Mike asked, "Have you been to Taiwan?"
Tell me who the person over there is.
Do you know who the person over there is?
I don't know what time it is.
Do you know what time it is?
Tell me if she will buy it.
Mike asked whether I had seen Tom the day before.
Mike asked whether I had been to Taiwan.