sniff out

基本解释

Still widely used, this electronic nose is able to sniff out a few parts per trillion of chemicals found in the soil, water or air.
这种仪器直至今天仍然广泛使用，它可以从土壤、水或空气中发现的数以万计的化学物中嗅到一部分（需要的）的东西。
Mosquitoes behind malaria follow carbon dioxide exhalations until they're close enough to sniff out our feet, a strategy that researchers hope to exploit to stop them.
传播疟疾的蚊子在近距离闻到我们脚丫的气味之前，根据二氧化碳呼出寻找目标。研究人员希望利用这些来对付蚊子。
If anyone makes it past all these obstacles, there are checkpoints at the bus station, at railroad yards and on the main roads out of town, complete with dogs to sniff out stowaways.
如果有人最终克服了这一切障碍，他还要面对的是，在公交车站，火车站，城镇主要大道上充斥着检查站，检查站满是用以寻找偷渡者的警犬。

You're on the phone with this guy all the time and you sniff something out, you can maybe stop it.
如果你和某人经常通话联系,并且嗅出了问题,你也许就不会借钱给他们了
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I took my role to sniff that out, and to make sure the president heard 2 and 4 on an important issue, and was able to make the decision himself.
我的作用就是发现这些，保证总统可以听到2和4这两个观点4,在一些重要问题上，然后他能自己做决定。
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That means people are able to sniff out suitable MHC genomes in prospective partners.
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Moreover, dogs have been trained to sniff out DVDs for raids on large bootlegging operations.
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If you sniff out something, you discover it after some searching.
When a dog used by a group such as the police sniffs out hidden explosives or drugs, it finds them using its sense of smell.