A complete safety check was performed on the aircraft prior to takeoff.飞机起飞前作了彻底的安全检查。The band played a final gig before splitting up.乐队散伙前作了最后一次演出。She pirouetted in front of the glass.她在镜前作单脚尖旋转。It's a capital mistake to theorize before one has data.在获得数据前作理论推断是非常严重的错误。