An informer is someone who secretly tells the police, the army, or another official group about people who are breaking the law. Very often they do it for money, or because the police have promised to go easier on them.

An informer is someone who secretly tells the police, the army, or another official group about people who are breaking the lawinformer是那種偷偷向警察、軍隊，或其他官方單位告發違法者的人。Very often they do it for money他們常常是為了錢, or because the police have promised to go easier on them或因為警察答應會對他們從輕發落。

The word feels cold, even ugly: an informer is not a brave witness in court, but a person who talks behind someone’s back.

The word feels cold, even ugly這個字聽起來很冷酷，甚至有點難聽: an informer is not a brave witness in courtinformer不是法庭上勇敢作證的證人, but a person who talks behind someone's back而是在背後說人壞話、出賣別人的人。

Though actually, the same person may be called an informant in police talk, which sounds cleaner and more like a job. Friends and family usually say it with anger.

Though actually不過其實, the same person may be called an informant in police talk同一個人在警方的說法裡可能被叫做informant, which sounds cleaner and more like a job聽起來比較乾淨、比較像一份工作。Friends and family usually say it with anger朋友和家人通常會帶著憤怒說出這個字。

You will hear it in crime news, spy stories, and history — for example, someone who told the army where fighters were hiding.

You will hear it in crime news, spy stories, and history你會在犯罪新聞、間諜故事和歷史裡聽到這個字 — for example, someone who told the army where fighters were hiding例如，某個把戰士藏身處告訴軍隊的人。

It is not used for a person who simply gives you useful facts.

It is not used for a person who simply gives you useful facts這個字不會用在單純提供有用資訊給你的人身上。