riddle是Puzzle的壹種，比較幽默滑稽的那種。puzzle的概念大，riddle的概念小。所以詞典裏解釋是： A riddle is a puzzle or joke in which you ask a question that seems to be nonsense but which has a clever or amusing answer
A puzzle is a question, game, or toy which you have to think about carefully in order to answer it correctly or put it together properly.