1·The major factors affecting the stability of cave roof under pile in karst region are deeply analyzed.
对影响溶洞顶板稳定性的各种主要因素进行了深入分析。
2·I watched a second on a multi pitch climb drop his leader a long way and end up in pool of blood as he was lifted into a cave roof.
我看过第二攀登者在多绳距攀登时离他的先锋者很远一段距离，最后躺在血泊中，头撞到洞顶。
3·The safety factor of karst cave roof is defined as the ratio of actual shear strength parameter to critical failure shear strength parameter in this paper.
定义溶洞顶板稳定性安全系数为顶板岩体实际剪切强度与折减到临界破坏时的剪切强度之比值。
4·The limestone is sufficiently fissured for tree roots to have breached the roof of the cave.
石灰岩裂开了足以让树根突破洞顶。
—— 《柯林斯英汉双解大词典》
5·The most frightening thing was that all the roof panels were shaking like crazy. Everyone was looking up at the ceiling thinking it was going to cave in.
最恐怖的事情是所有的屋顶疯狂的摆动，每个人都看着天花板，想着它会不会破。
6·When did the roof cave in?
屋顶是什么时候坍塌的？
7·I went on walking, bending down because the roof of the cave was not very high.
我继续弯着腰往前走，因为岩洞的顶部不够高。
8·The roof is dangerous and could cave in at any time.
屋顶很危险，任何时候都可能坍塌。
9·When did the roof cave in?
屋顶有坍塌的危险。
10·First, based on similar material model test, top coal cave-in characters in steep and thick seam were studied as well as failure law of main roof and features of surface subsiding.
首先利用相似模拟实验研究了急斜特厚煤层顶煤的冒落特征、顶板的破坏规律，以及地表下沉的特点。