Second, because only male deer rub, the buck rub and its associated chemicals indicate the sex of the deer producing the rub.

第二，因为只有雄鹿会做出摩擦动作，摩擦动作和与之相关的化学物质表明了制造擦痕的鹿的性别。

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The hotel is in the middle of nowhere and there lies the rub. We don't have a car.

难就难在旅馆很偏远，我们又没有汽车。

《牛津词典》

Buck rubs also have a scent produced by glands in the foreheads of deer that is transferred to the tree when the rub is made.

雄鹿摩擦都有一种由雄鹿前额上的腺体产生的气味，这种气味在制造擦痕时就涂抹到了树上。

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The old couple smiled and cooled until the babies began to yawn and rub their eyes with tiny fists.

VOA: special.2009.02.28

Now those oligarchies were based on different things, and that's where the rub came.

但这些寡头是建立在不同基础之上的,正是这一点导致了双方的摩擦

耶鲁公开课 - 美国内战与重建课程节选

Every time I drive the steering wheel of my car, I rub off some items. But that's OK, it's still the very same physical object.

每次我使用方向盘时，都会摩擦掉一些微粒，但没关系，它还是原来那个物体。

耶鲁公开课 - 死亡课程节选

The rub is that the contraction is expected to intensify in the near term.

FORBES: Market Scan

But, and here's the rub, we were just a few hours south of Playa Bonfil.

BBC: Mexican rapes: 'I wish I didn't know the details'

But here lies the rub: providing funds that bypass the government is easier said than done.

ECONOMIST: How to prop up the government