There are guards at the door to keep out the undesirables.

门口有卫兵防止不良分子入内。

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We play our part too - during the Three Days of Darkness we will remove the undesirables.

我们也在做着我们这边的工作- - -在三天的黑暗时期我们将移除这些不良分子。

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Pillows -and the stuffy bedroom air that surrounds them -are ideal breeding grounds for undesirables ranging from the superbugs MRSA and C.diff to flu, chicken pox and even leprosy.

枕头及其周围不透气的卧室环境是超级病菌耐甲氧西林金黄色葡萄球菌和艰难梭菌，水痘甚至是麻风病这一系列破坏分子的理想滋生区。

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There are other points made there, that few spend beyond the discount coupon itself, few return without a coupon and that some current customers use the coupons, all undesirables for the merchants.

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Officials in Brussels say EU rules allow neither the setting of a minimum income nor the expulsion of undesirables from one member to another, save in very restricted cases.

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Iran, for its part, blames Pakistan for shunting undesirables across the common border.

ECONOMIST: Dealing with Iran