来自《耶鲁大学开放课程：心理学导论 第12集》

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  There are a lot of examples of this.
  这有很多例子
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  Animals groom one another.
  动物们互相照顾
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  You go, you pick off the lice and the bugs off your friend;
  你会把虱子和虫子从你朋友的身上抓走
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  they pick it off you.
  他们也会帮你抓走
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  They give warning cries.
  动物会发出危险警告
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  So, warning cries--All sorts of animals give warning cries.
  危险警告 很多动物会发出危险警告
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  You are--I don't know.
  假设你是 我不知道
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  You're a little animal and a big animal comes charging
  假设你是个小动物 大的敌人来了
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  and you say, "Hey!"
  你会喊 喂
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  Oh. You may sort of cry and everybody runs away.
  你会喊叫 然后大家闻风而逃
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  And that's very risky for you
  这对你很危险
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  but you do it anyway,
  但你还是会做