A joist is any of a series of small parallel beams supporting a floor or roof. 托梁是一系列的小列柱梁,用以支撑楼层或屋顶。
The floor joist was cracked and fractured, but no debris was deposited in the basement, as the subflooring remained intact. 地板托梁破裂折断,但是在地下室并未落下碎片因地板下面安然无恙。