<human>: Hello r/dogs! I have had my pup for 3 and a half weeks. The first two weeks I started housebreaking him by crate training, and it has worked perfectly. Ever since I stopped crate training, he has had much more freedom, but I have a bigger problem. Every time myself or my girlfriend try to pet him, he begins biting. I know that he is teething, so I always supply him with something cold to naw on (frozen carrots have worked amazing!), but it still never fails that whenever I put my hand near him he begins chewing on me, a lot of times HARD! I have tried many methods to try and curb him from doing this, such as yelping when he bites, holding mouth shut for a few seconds, softly pushing tongue down when he bites, and the vet suggested putting him into a submission hold. My girlfriend is on her last leg with him (she's never owned a puppy before), and I absolutely do not want to get rid of him, but I am at a loss. Are there any methods that you guys used that worked like a charm? Any advice will be much appreciated!

Can you condense the text into a few key points?
<bot>: 9 week old pup constantly bites on me, have tried many methods to stop it, but to no avail. Need advice for how to curb this habit.