in concert (with somebody)

a) formal people who do something in concert do it together after having agreed on it （与某人）一起〔行动〕

Britain has to pursue policies in concert with other EU members.

英国必须和其他欧盟成员国一起贯彻各项政策。

It appeared that both the accused were acting in concert in the attack upon the deceased.

两名被告看来是合力袭击死者的。

b) APplaying or singing at a concert 在音乐会上演出

They’re appearing in concert tonight at the Royal Concert Hall.

他们今晚将在皇家音乐大厅登台演出。

Examples from the Corpus

acting in concert• In so doing he seems to have been acting in concert with a Roman official called Seronatus.• The Regulation also applies to the acquisition of joint control by a number of companies acting in concert.• The calcium waves spreading through glial cells may constitute a long-range signalling network acting in concert with conventional neuronal networks.• The concert party provisions apply equally to the directors of the target and persons acting in concert with them.

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