1、一:名词(一般有三个大方面的意思)1,目击者 固定词组 witness ofwitnesses(at the scene) of the accident 事故(现场)的目击者I was a witness to their quarrel. 我是他们吵架时的目击者.(注意,后面这个witness to 不是词组.但常用)2,证人a defence/prosecution witness 被告的/原告的证人 a witness for the defence/prosecution 被告的/原告的证人(注: witness for也不是词组,只是一般后面跟for)3,证明,证据give witness on behalf of an accused person 为被告方作证 His ragged clothes were (a) witness to his poverty. 他的破烂衣物可以证明他很贫穷. (他的破烂衣服是他贫穷的一个证明)二:动词1,目击(当场见到某事物)witness an accident, a murder, a quarrel 目击一事故、 谋杀事件、 一场争吵We were witnessing the most important scientific development of the century. 我们亲眼见到本世纪最重要的科学进展. Weather forecasters are not always right: witness (ie look at the example of) their recent mistakes. 天气预报并非一贯正确--就看看他们最近的预报错误吧.2,为别人签署（文件）时作证（尤指自己也同时签字者）witness the signing of a contract 在一份合同签署时作证 witness a signature, treaty, will 为一签字、 条约、 遗嘱签字作证.3 ~ to sth （在法庭等上）作证witness (ie testify) to the truth of a statement .(witness to不是词组) 固定词组只有witness of,经常与to,for接.但不是固定.