You can avoid the single supplement by agreeing to share a twin room.

你如果同意与人共住双人房就可免交单间附加费。

《柯林斯英汉双解大词典》

Have you booked a twin room in West Hotel for our holiday?

你是否为我们的假期预订了西部酒店的双床房？

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Good Morning. I want to book a twin room.

早上好，我想预定一个双人床的房间。

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They plan to build a twin tower consisting of a 326-room hotel and a 46, 000-square-foot medical center.

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He has twin 8-year-olds, and they need some elbow room, he says.

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But many of the other rooms are not--you can comfortably play billiards on the fine English table, a twin of one at Buckingham Palace, but the library or Jade Room may get a bit sticky.

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