服务员对人性的观察非常敏锐，察觉到了这种情况。在一次民意调查中，有足足30％的服务员认为，自己的工作情况对收到多少小费没有任何影响。

Waiters, keen observers of humanity that they are, are catching on to this; in one poll, a full 30% said they didn't believe the job they did had any impact on the tips they received.

youdao

熊猫有非常敏锐的嗅觉。

Pandas have a very keen (敏锐的) sense of smell.

youdao

虽然人类的嗅觉能力确实不如某些动物灵敏，但也是非常敏锐的。

While it is true that the olfactory powers of humans are nothing like as fine as those possessed by certain animals, they are still remarkably acute.

youdao

> Very observant.

>，非常敏锐的。

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