It's a lancet fluke: it's a little brain worm — a parasitic brain worm — that has to get into the stomach of a sheep or a cow in order to continue its life cycle.

这是一种枝双腔吸虫(lancet fluke)，它是一种很小的活在大脑里的虫子，一种大脑的寄生虫，它必须要进入到绵羊或奶牛的肚子里才能继续活下去。

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And the sheep answered, "we would have been honoured to visit your house if it were not in your stomach."

羊回答说：“我们将以造府为荣，如果贵府不是在你肚子里的话。”

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