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- He wore a mask so that no one should recognize him. 他戴了一个面罩，使别人认不出他来。
- adult tracheostomy mask 成人气管切开术面罩
- tracheostomy mask 气管切开术用面罩
- Sham is sham and the mask must be stripped off. 假的就是假的，伪装应当剥去。
- He tried to mask his disappointment with a smile. 他试图以微笑来掩饰他的失望。
- The mask fitted tightly over his face. 他用面具把脸蒙得严严的。
- They did so under the mask of charity. 他们是打着慈善的幌子这么做的。
- Such feelings tend to remain submerge beneath a mask of social politeness. 在社交礼貌的掩盖下，这样的情感往往不会显露出来。
- To replace a standard tracheostomy tube. 替换一般标准型气切管。
- Her sociable manner is really a mask for a very shy nature. 她那好交际的作风，实际上是她腼腆天性的伪装。
- For a moment his mask of benevolence fell and the real man was revealed. 一刹那间，他慈善的假面扔掉，露出了他的真面目。
- A base, ungenerous wretch who under the mask of friendship has undone me. 有个卑鄙、吝啬的家伙打着友谊的幌子把我毁了。
- A mask, in the character of an old woman, joined them. 一个戴着假面具扮演老妇的人加入了他们的行列。
- He preserved his mask of solemnity even with acquaintances. 他甚至和熟人交往也保持着一本正经的面孔。
- He conceals his worries behind a mask of nonchalance. 他装作若无其事，藉以掩饰内心的不安。
- An oxygen mask will come down from overhead in case of an emergency. 若发生紧急情况，头顶上会降下一只氧气面罩。
- We tore from them the mask of democracy. 我们撕下了他们民主的假面具。
- Pediatric tracheostomy tubes are usually not cuffed. 儿科用的气管切开术插管常常没有管口的翻边。
- If air is needed, the oxygen mask in the plane will pop down by itself. 如果空气缺乏，飞机内的氧气面罩会自动放下。
- They contrived a mask against poison gas. 他们设计了一种防毒面具。
