In Britain, a by-election is held when a Member of Parliament dies, retires or resigns.

英国的下院议会成员中有人去世、退休或辞职时，就要进行补缺选举。

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Members of the House of Commons are elected either at a General election, when all the seats are contested, or at a by-election held when an MP dies or resigns, or is given a peerage.

下议院议员或经过所有的议席都可竞争的大选选出，或是在议员去世，辞职或者受封为贵族时经补缺选举而产生。

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Article 19 a by-election can be held by the villagers' assembly or the villagers' representatives' assembly if there is any vacancy in the villagers' committee.

第十九条村民委员会成员出缺，可以由村民会议或者村民代表会议进行补选。

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In the event of the death of one of them, a by-election is held in which other hereditary peers belonging to the same party as the deceased can stand.

BBC: Viscount Ridley

It is not clear when a by-election will be held but the prospect will be an unwelcome one for Gordon Brown, left reeling by the expenses scandal and the spate of cabinet resignations in the past few days.

BBC: MP quitting to force by-election

Assuming a presidential election is held in June, and that Mr Karzai wins, he could be obliged to rule by decree for almost a year.

ECONOMIST: Can the elections be held on time?