A five o'clock shadow is facial stubble. It sometimes describes a man's beard at the end of the day.

Five o'clock shadow是指胡子，就是男生一天下来，到下午五点就会长出来的一点点胡子。

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A five o'clock shadow is facial stubble, it sometimes describes a man's beard at the end of the day.

原来five o'clock shadow是指胡子，就是男生一天下来，到下午五点就会长出来的一点点胡子, 所以人们就用five o'clock shadow来形容男生脸上的胡子茬子。

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The gaffes surrounding such debates have become part of the folklore of American presidential elections ever since Richard Nixon's five o'clock shadow is said to have lost him the 1960 presidential race.

ECONOMIST: TV debates