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- Difficult mining layer 难采煤层
- 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。
- Ground pressure of top-coal caving face in difficult mining steep coal seams 急斜难采煤层水平分层放顶煤开采矿压研究
- He went heels over head into buying mining stock. 他购买了矿业股票，做事真鲁莽。
- 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。
- She handled a difficult argument skilfully. 她巧妙地应付了一场艰难的辩论。
- 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。
- It is difficult to keep on terms with such a man. 很难和这样的人保持友好关系。
- This area depends on the mining industry. 这个地区以采矿业为经济基础。
- It is difficult to stamp out all the crimes. 很难把所有的犯罪都消除掉。
- He tried gold mining, pearling and fur trapping. 他尝试过淘金，采珍珠和猎兽皮。
- It's difficult raising a family on a small income. 依靠微薄的收入是很难养家的。
- He was trained there as a mining engineer. 他在那里被培养成一名采矿工程师。
- He is unable to do such a difficult job now. 他现在还不能做这样困难的工作。
- She can play the most difficult piano music by ear. 她能不看乐谱，光凭听觉记忆弹奏最难的钢琴曲。
- The past month has been a difficult one for him. 上个月他很困难。
