Some changes happen only once in a while, like an eclipse of the moon.

一些变化只有某个时候才会发生，比如月食。

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Previously I saw him very often but now he comes here only once in a while.

以前我常常看到他，可是现在他只是偶尔来一次。

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It is said a little separation is better for the newly wedded. They meet only once in a while, but find it very sweet.

俗话说久别胜新婚，他们虽然很久才见一次面，但却十分甜蜜。

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Censorship only comes into play once a text has actually been in circulation for a while, only after a number of readers have found a published text to pose a threat.

控制仅仅是一本书已经出版发行一段时间,一些读者已经发现这印刷的文本,造成威胁时才起作用的。

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But only once in a very long while do I come across a company that has held and maintained a tangible product advantage over the long haul.

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And they got used to keeping the land undeveloped so long as the only effort needed was to quash anyone rising his head once in a while.

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To protect his family during the SARS outbreak, Dr. Lee moved out of his apartment and lived in self-imposed quarantine for months while treating patients, seeing his wife and young son only once a day through the grille of a metal door when they came to drop off his dinner.

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