three-line whip

noun

1. 紧急通知（英国政党领袖要求其议员必须参加投票和如何投票的书面通知）
   (in Britain) a written notice to Members of Parliament from their party leaders telling them that they must be present at a particular vote and must vote in a particular way

1. (要求某政党议员参加议会并按照要求就某议题投票的)紧急指令
   A three-line whip is a situation where the MPs in a political party are ordered to attend parliament and vote in a particular way on a particular issue.

1. First, it exposed the scale of Euroscepticism in the Tory party: 81 of its MPs defied both Mr Cameron's pleas and a three-line whip to support the motion.
   首先，它暴露出保守党内部有相当数量的反亲欧派存在：81位保守党议员不顾卡梅伦的再三呼吁和一再谴责，执意提出这一议案。