n (1)难题，难以理解或回答的问题，难解之谜 (question difficult to understand or answer; mystery) [C， 通常sing]： The murder case was a～to the detective. 那件谋杀案对侦探来说是个难题。Her decision was a～to me. 她的决定我很难理解。the～of how life began 生命起源之谜;The motives of the film-makers remain a～. 电影制片人的动机仍然是个谜。〖同〗mystery，problem，riddle;

(2)测验智力的游戏或玩具(kind of game or toy to test sb's thinking， knowledge or skill) [C] (常用于合成词)： crossword～s 纵横字谜;a jigsaw～拼图玩具;find the answer to/solve a～猜出谜底/解开一个谜;set a～for sb (set sb a～) 给某人猜一个谜;a book of～s 谜语书;

v (1)使困惑(苦思) (cause (sb) to think hard)[T+n]： His reply/Something in his voice/His recent behaviour～d me. 他的回答/他声音里的某种东西/他最近的行为使我困惑不解。be～d by sb's failure to reply/refusal to help 由于某人未作回答/拒绝给予帮助而困惑不解;The murder case continue to～the police. 那件谋杀案仍使警察感到困惑不解。～one's brains to find the answer/about sth 绞尽脑汁寻找答案/为某事大伤脑筋;be～d about what to do next/how to react 不知下一步该做什么/如何作出反应;〖同〗confuse;

(2)苦苦思考(think deeply about sth in order to understand it) [I+prep (over)]：～over a problem/one's arithmetic/sb's strange behaviour/sb's strange letter for several hours对一个问题/算术题/某人奇怪的行为/某人奇怪的信苦苦思考了几个小时;I've been～ing over how the dog got into the house. 我一直在苦苦思考那狗是怎么进屋的。

(3)苦思而解决，设法想出 (find the answer to sth by thinking hard) [T+n+adv(out)]：～out the answer to the problem/the meaning of the cypher 思考出问题的答案/密码的意思;I've tried for hours to～out what could have made him so angry that he hasn't written to us. 我想了好几个小时，终于想出了可能使他生气而不给我们写信的原因。

→′puzzled adj 迷惑不解的;′puzzler n 令人迷惑不解的人或物;′puzzlement n 困惑;′puzzling adj 令人迷惑不解的