Trip to mexico!help!!?

Question

OKAY, SO I HAVE A CHANCE TO GO TO MEXICO FOR A MONTH, WHICH IS GREAT BECAUSE I LOVE GOING THERE. BUT THERES JUST ONE PROBLEM, IM NOT SURE IF YOU NEED A PASSPORT TO GET BACK TO THE U.S, ALSO I WOULD BE TAKING A BUS KINDA LIKE THE GREYHOUND THAT SPECIALIZES ON TRIPS TO THE PART OF MEXICO WERE IM GOING ON VACATION.SO WHEN IM BACK FROM MY TRIP IM NOT SURE IF THEYLL LET ME BACK FOR M MEXICO!

Answer 1

You need a passport. See INS.com

Answer 2

Do you need air to breath?

DOOOH!

Passport is not only a document for crossing borders, is usually a great ID that can get you out of lots of trouble specially if you need assistance from the US embassy when in trouble.