She refused to testify against her husband.

她拒绝出庭作证指控丈夫。

《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》

One witness will testify against her and two will on her behalf.

一位证人将作不利于她的证明，另外两位将作有利于她的证明。

youdao

However,the judge told the prosecution to continue lining up witnesses to testify against Kasab, saying his trial will continue.

VOA: standard.2009.07.23

Each day, prison buses route inmates from prisons to courtrooms to testify against co-conspirators.

FORBES: Will Rajaratnam Testify in Rajat Gupta Case?

All but Shea are cooperating with federal authorities and are likely to testify against the defendants.

FORBES: Forget The Galleon Group Trial(s) -- Sky Capital Will Be The Trial of 2011

Former friends, business colleagues and FBI agents are slated to testify against Rajaratnam in court.

FORBES: Galleon Group Trial Hits The Courtroom: The U.S. Vs. Rajaratnam