The president hopes that the people will be better off when he quits than when he      .

A．has started

B．starts

C．started

D．will start

建筑安全技术

以下不属于建筑施工过程中“五大伤害事故”的是( )。

A．高处坠落

B．机械伤害

C．起重伤害

D．坍塌