quid pro quo
noun[Cusually singular]
formaluk/ˌkwɪd prəʊ ˈkwəʊ/us/ˌkwɪd proʊ ˈkwoʊ/pluralquid pro quossomething that is given to apersoninreturnfor something they have done:
交换物;报酬;交换条件Thegovernmenthaspromisedfoodaidas aquidproquoforthestoppingofviolence.政府许诺以食品援助作为停止暴力活动的交换条件。