witness tosth
—phrasal verbwithwitnessverb[T]uk/ˈwɪt.nəs/us/ˈwɪt.nəs/
UKformalto saypublicly,especiallyin alawcourt, that something istrueor that ithappened
（尤指在法庭上）作证，证明…是真实的
Ahandwritingexpertwitnessedto theauthenticityof theletter.笔迹专家证明了这封信不是伪造的。
[+ -ing verb]Shewitnessedto havingseentherobberytakeplace.她作证说目睹了抢劫的过程。