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- difficult caving roof 难垮落顶板
- Because the increase of mining height in fully-mechinzed coal winning caving roof,it brings convenient and both brings the changing of rock rationlations. 大采高综放工作面由于机采高度的加大,在给工作面生产带来便利的同时,也带来支架与围岩关系的变化。
- fully-mechanized coal winning caving roof face 综放工作面
- support at fully-mechinzed coal winning caving roof 综放支架
- Keywords inducation caving roof;RFPA;time-varying effecting;empty; 顶板诱导崩落;RFPA;时变效应;采空区;
- The roof is dangerous and could cave in at any time. 屋顶很危险，任何时候都会坍塌。
- mining height fully-mechanized coal winning caving roof 大采高综放
- Study on the contool of top coal depletion ratio in caving roof mining 放顶煤开采顶煤贫化率控制研究
- It must be difficult to play various personae in the same movie. 在同一个电影中扮演不同的角色肯定不容易。
- Navigation is difficult on this river because of the hidden rocks. 因为河上有暗礁，所以在这条河上航行很困难。
- It was difficult to tell his exact age. 很难判断他到底多大岁数。
- The roof of the old house will cave in any time. 这所老房子的屋顶随时会塌下来。
- It is difficult to express it in terms of science. 要用科学的字眼来表达它是很困难的。
- It was difficult to gauge how people would respond. 大家的反应如何难以估计。
- A hermit used to live in the cave. 一位隐士曾经住在那个山洞里。
- She handled a difficult argument skilfully. 她巧妙地应付了一场艰难的辩论。
- We kindled a firebrand in the cave. 我们在山洞里点燃火把。
- A mouse ran out from the dark orifice of the cave. 一只老鼠从黑暗的洞口跑出。
- He find it difficult to give shape to his idea. 他觉得很难把他的想法，明确表达出来。
- It is difficult to decide between the two opinions. 在这两种意见之间抉择是困难的。
