When Google would nip at me, I would say "OW!" really loud, then stop playing with him immediately. I'd ignore him for about a minute (puppies have short attention spans) then I'd resume. (The "ow!" has to be loud enough to startle him!)
He no longer nips at me, and even lets me put my hand in his mouth when I have to look at his teeth. My kids and husband, who did not do this as I did, still have him playing too rough with them on occasion. I think, Google thinks that Mommy has really sensitive skin and his teeth can't touch her skin or she gets hurt, but EVERYONE ELSE is OK to nip at!
