"You are Peter."

[Hanna704113]

Why can't it be तूम पीटर हो?

[TonDieu]

Tum Peter ho, is correct. In fact, it is more appropriate than 'tu peter hai'. Tu is a singular used only among friends. It is definitely not used when meeting people for the first time.

[Rishabh135790]

तू पीटर है would come as quite rude with strangers

[another-dave]

So would telling them their name imstead of asking it :)

[_Higher_]

As funny fact, तू sound exactly the same as spanish Tu and both means You in english :D