The curfew regulation is a temporary expedient made necessary by a sudden emergency.

宵禁令是应对突发事件时必要的临时权宜之举。

《柯林斯英汉双解大词典》

At times of sudden emergency in schools, kindergartens, nurseries, and public places minors are to receive aid.

学校、幼儿园、托儿所和公共场所发生突发事件时，应当优先救护未成年人。

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There may be a sudden emergency like an animal on the road, or you may not be quite sure what another driver is going to do.

可能会出现突发紧急状况，比如，动物上路，或您可能不确定另一个驾驶员想干什么。

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That night she experienced a sudden health issue and went into emergency surgery.

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And that's why the federal government provided General Motors and Chrysler with emergency loans to prevent their sudden collapse at the end of last year -- only on the condition that they would develop plans to restructure.

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Last year, an A330-303 was forced to make an emergency landing in Australia after a sudden change in altitude injured 74 passengers.

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