A fox USES its tail (or "brush") as a warm cover in cold weather and as a signal flag to communicate with other foxes.

狐狸用它的尾巴(或“毛刷”)在冷天时盖上保暖，同其他狐狸交流时亦可用来做信号旗。

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His ears are cold. His nose is cold. His tail is cold.

它的耳朵冷。它的鼻子冷。它的尾巴冷。

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A fox has a big, bushy tail. This is a good tail to have on cold nights.

狐狸也有一条大的、绒毛浓密的尾巴，这条尾巴在寒冷的夜晚真是有用极了。

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When humans blossomed from the evolutionary tree, it seems there was a cold wet nose and a wagging tail waiting for us.

CNN: Quest for man's best friend