甲烷

It's his job to sniff out abuses of power. 他的职责就是查究滥用权力的行为。

He cleared his nose with a loud sniff. 他大声吸气清了清鼻子。

My roommate sniff at my idea of becoming an artist. 我的室友对我要当艺术家的想法嗤之以鼻。

It's their job to sniff out abuses of power. 他们的工作是对滥用职权的情况进行调查了解。

Don't sniff at his effort. He's made great progress. 不要看不起他的努力。他已经取得了很大的进步。

One sniff of this is enough to kill you. 此物闻一闻即足以致命。