Capital punishment is allowable only under exceptional circumstances.

只有在特殊情况下才允许判死刑。

《柯林斯英汉双解大词典》

Fees paid are not refundable, except under exceptional circumstances.

除特殊情况外，一切已缴费用，概不退还。

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Waivers. Waivers or exceptions to the Code may only be granted in advance and only under exceptional circumstances.

针对本准则的免责或例外仅仅是在提前授予和在某些特殊情况下适用。

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He said pregnant women should only be held at the centre under exceptional circumstances and changes were needed despite recent improvements.

BBC: Yarl's Wood: 'Too many pregnant women held'

Under European Union rules, EU governments are forbidden from subsidising struggling companies that could give them an unfair advantage over rivals except under exceptional circumstances.

BBC: EU presses Italy on Alitalia loan

Councillor Bert Biscoe said 56 facilities where "exceptional circumstances" had been identified would remain under the control of Cornwall Council.

BBC: Public toilets, Cornwall