用作名词
1.目击者 固定词组 witness of
witnesses(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。
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。