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- difficult degradation wastewater 难降解废水
- The treating trend for the difficult degradable organic pollutants such as dyeing wastewater was discussed. 探讨了印染废水等难降解有机污染物处理的发展趋势。
- During the bacteria treatment, because of unique difficult degrading of phenolic wastewater, involving high efficient bacteria is a question that people always care. 在生物处理过程中，由于含酚废水的独特的难降解性，引入高效菌种是人们一直关心的问题；
- 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。
- Being sent to prison was the final degradation. 堕落到最后地步就是被关进监狱。
- It was difficult to tell his exact age. 很难判断他到底多大岁数。
- 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。
- Coking effluent is a typical and difficultly degraded effluent that contains high concentration of organic pollutants. 焦化废水是典型的含高浓度有机污染物的难降解废水。
- 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。
- It is difficult to stamp out all the crimes. 很难把所有的犯罪都消除掉。
- It's difficult raising a family on a small income. 依靠微薄的收入是很难养家的。
- 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。
- The stain on his shirt is difficult to clean off. 他衬衣上的污点很难去除掉。
