a wise guy

a wise guy 经常听到“don't be a wise guy”,怎么翻译比较好? a wise man 和 a wise guy 有什么区别啊?好像是意思相反的 可我查的时候 没查出来a wise guy 的意思 ,a wise man 是哲人、魔术师的意思.哪个对阿.....-_-； tell me how come this would happen?for what reason does quicksand flow slowly,slim chance equals to fat chance and a wise man and a wise guy are the opposites?why? a stupidly good guy Are u a guy? A go-to guy guy guy A wise choice is yours He is a label guy. He is a fantastic guy. YOU MEET A GOOD GUY a guy about 5'10 请翻译：a little guy I am a stupid guy A Guy Like You 歌词 No man is born ( ), we need to learn to become ( )A wise wise B wisely wise