GET D!RTY! Next time you're signing with your friends, drop the ASL textbook formality and start flashing the signs they don't teach in any classroom, including: * cool slang * funny insults * explicit sex terms * raw swear words Dirty Sign Language teaches casual everyday words and expressions like: * Peace out! * Asshole. * Bit me! * Dumbfuck! * Boner * I'm hung like a horse.