The floor began to descend on a powerful hydraulic press until it locked into place.在大功率液压机作用下，地板开始降落，直至到达指定位置。The plane had already started its descent when the pilot received orders to abort his landing.飞机已经开始降落，可这时飞行员接到命令，要求终止着陆。The airplane began to descend as it neared the island.飞机接近这座岛时开始降落。