My mother, who is just shy of five feet tall, is normally incredibly soft-spoken, but on the rare occasion when she got angry, she was terrifying.

我的母亲只有不到五英尺高，平时说话非常温和，但极少数生气的时候，她会表现得很可怕。

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But sometimes, on the rare occasion, Gaga breaks out a "normal" looking outfit — an average-length dress, pants — and shocks us even more.

不过有时候，嘎嘎却极其罕见地以一身“正常”行头出镜——穿起了长裙长裤——这反倒更让人大跌眼镜。

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At the home, we all wanted to escape, and on the rare occasion a parent surfaced they could take you out for a few hours.

住在那的人都想逃出去，父母露面的机会虽极少，但他们能把你带出去呆几小时。

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So on the rare occasion when Merkel says something vivid, something important must be going on.

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On the rare occasion he loses, his bodyguards have been known to open fire on the crowds.

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On the rare occasion when America has truly vital interests at stake, military action may be justified.

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