He was summoned to testify before a grand jury.

他被传唤出庭在大陪审团前作证。

《牛津词典》

He made a deal to testify against the others and wasn't charged.

他达成了协议出庭指证别人，因而未获指控。

《柯林斯英汉双解大词典》

Several researchers write, speak and testify quite a lot on the threat posed by violence in the media.

几位研究人员就媒体暴力所造成的威胁进行了大量的写作、发言和证实。

youdao

During a trial, lawyers for the opposing sides question the witnesses who testify.

VOA: special.2009.08.31

And not a single young person in the room except my son, who was then a teenager who would tag along and see his father testify.

却没有一个年轻人在场,除了我儿子，是当时唯一的青少年,除了他没人跟着父亲参加听证会。

麻省理工公开课 - 媒体、教育、市场课程节选

who is one of the plaintiffs and expected to testify in a class action lawsuit.

VOA: standard.2010.03.26

Rows of walled-off houses and small hotel complexes, most with a deliciously inviting pool just visible through a gate, testify to a place that takes its undisturbed leisure very seriously.

BBC: The perfect trip: Southwest USA

Nevertheless, Wolk on Wednesday had his lawyers, who are partly being financed by Elliott Management, arrange for Lee to be served with a subpoena to testify in a deposition and turn over documents this month.

FORBES: Hedge Fund Elliott Management Is Backing Stan Lee Media's Spider-Man Lawsuit Against Disney

In the conversation, Mr Singh apparently tells Mr Chandra how a prosecution witness would testify in a special court which is hearing the case.

BBC: India's CBI removes telecoms scandal prosecutor