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- It is necessary that he be sent there at once. 有必要马上派他到那里去。
- She writes to her parents once a week. 她每周给父母写一封信。
- More than once I've felt my heart slip a cog. 我不止一次感到心脏突然停跳一下。
- My inn had once been a part of an ancient ecclesiastical house. 我的客栈曾经是一个古老教会的房子的一部分。
- He and I were shipmates on a trawler once. 我与他一度同在一艘拖网船上工作。
- It was once thought unmanly not to drink and smoke. 身为男子不抽烟不喝酒曾视为无男子气概。
- The flue should draw better once it's been swept. 烟道一经清扫，通风情况应好些。
- You'll like her once you get to know her. 你一旦了解她，就喜欢她了。
- He likes to hit the bottle once in a while. 他喜欢偶尔喝得酩酊大醉。
- She looked in on us [at our office]once in a while. 每隔些时候，她都到我们这儿[办公室]来一趟。
- I've decided to break with Silvia once and for all. 我决定同西尔维亚彻底绝交。
- Once I took a wife I should have to put down roots. 我一旦娶了老婆，就该过安定的生活了。
- Barry only visits his parents once in a blue moon. 巴里很难得去看望他父母一次。
- The leap year comes around once in four years. 每四年有一个闰年。
- Such evil practice cannot be swept away at once. 这种坏事不是一下能扫除干净的。
- The teacher asked the pupils not to speak at once. 老师叫学生们不要同时说话。
- I have seen this happen more than once. 发生这种事我屡见不鲜。
- At once he slew him and set Io free. 他立刻杀死了阿尔戈斯，放掉了伊俄。
- Once installed, this heater operates automatically. 一旦安装好以后，这加热器就会自动地运行。
- Alaska was once possessed by Russia. 阿拉斯加一度曾是俄国的领土。
