1) 때리다 and 치다 - They both mean to hit someone, but 때리다 is more specific than 치다. Beyond hitting someone to inflict pain, 때리다 can mean figuratively hitting someone (불길한 생각이 머리를 때리다). 치다 can also mean light tapping (내 어꺠를 툭 쳤다) as well as playing certain ball games (테니스/골프/탁구를 치다) and other things. 2) 고붙치다 and 곱놓다 - both are old words almost dying out completely. 고붙치다 is supposed to mean repeatedly folding something (e.g. a piece of fabric) into a neat shape, but it seems more often used nowadays as slang for stashing something hidden away from others (often said as 꼬붙쳐 놓다). 곱놓다 is listed in the dictionary as doubling one's wager in gambling, but I've never heard it said or read it even once. People would say 더블로 가다/놓다 or something similar to mean that. 3) 물다 and 깨물다 - while both primarily mean "to bite", 물다 has a broader usage and can have a figurative meaning of catching or holding onto something as a slang term (e.g. 물주를 하나 물었다 = I found/caught a rich guy I can suck money from). 깨물다 is strictly biting something, where 깨 indicates using the mouth and teeth. 4) 피를 쏟다 and 사혈하다 - 피를 쏟다 means to spew out blood, and is a fairly common expression. 사혈하다 is a rare word only used in traditional medicine (한의학) which means drawing blood using an acupuncture needle. Most ordinary people probably don't know this word.