但谁又敢说它们咀嚼的树木中也会含有那种防止羊吃人的未知细菌呢？

But who's to say the trees they chew don't contain some unknown bacterium that stops sheep becoming man-eaters?

youdao

但谁又敢说它们咀嚼的树木中也会含有那种防止羊吃人的未知细菌呢？

But who's to say the trees they chew don't contain some unknown bacterium that stops sheep becoming man-eaters?

youdao