Proper usage: (Stung) "I was stung by a bee." "Ouch! That stung." Sometimes used with friends in a joking sense. (Stab) This one is used in a more serious or violent situation. Generally referring to a knife. E.g. A mugger might say; "Give me your wallet, or I'll stab you." (Poke) Used in a much lighter sense. Literal use: "I poked him." (Implying a simple jab of the finger.) A parent might say "Those boys are always poking fun at each other." (A way of saying they make fun of each other.) (Stick) This word, unlike the others, is generally a noun. E.g. "I see a stick on the ground" Or "I poked him with a stick." Though it may be used like so: "Stick it to him!" or "Stick him with it!" Personally, I don't see it used like this much, other than in the occasional movie. As far as I know, it's not actually proper English either.