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Yeah, but he did have to have a bunch of stitches and he said that only once in a blue moon does a dog's ear grow back, so still hoping.
可是他必须帮它缝好多针，而且他还说只有出现蓝月亮时狗才会再长出耳朵来的，所以还有一点点希望。
《Friends Season 2》《老友记 第二季》
双语例句
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She has been beaten only once in six starts.
她参加了六次比赛，只败过一次。
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Ann wore it only once.
安只穿过它一次。
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The operation should be done only once for each mode.
此操作对于每个模式来说只进行一次。
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This is why many viruses, such as measles, make us ill only once.
这就是为什么许多病毒，如麻疹，只会使我们生病一次。
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An episode of major depression may occur only once in a person's lifetime, but more often, it recurs throughout a person's life.
重度抑郁发作可能在一个人的一生中仅出现一次，但更经常的是，它在一个人的一生中反复出现。