电梯坏了,所以我们不得不爬一段楼梯。
Due to the broken lift, we had to ascend a ___flight of stairs.
他因为让她从一段楼梯上摔下来而自责。
He blamed himself for the accident where she fell down a ___flight of stairs.
有一段螺旋楼梯通向屋顶。
There is a spiral ___flight of steps leading to the rooftop.