What Does “Inform on sb” Mean?
“Inform on sb” means to tell someone, often an authority, about another person’s wrongdoing or secret actions. It usually involves reporting someone to the police or another official group.
Introduction
The phrase “inform on sb” is commonly used in English to describe the act of reporting someone’s behavior, especially when it is secret or illegal. The “sb” stands for “somebody,” meaning you inform about a person. Understanding the “inform on sb meaning” helps learners use this phrase correctly when talking about situations involving reporting or giving information about others. It is often used in legal and everyday contexts where someone shares important details about another person’s actions to an authority or organization. This phrase has a serious tone and is not usually used in casual conversations.
Quick Info Box
- Phrasal verb: Inform on somebody
- Type: Transitive
- Level: B2
- Short meaning: To report someone’s bad or secret behavior to authorities
Structure (Grammar Rules)
“Inform on sb” is a transitive phrasal verb, so it needs a direct object (the person you inform about).
- It is inseparable; you cannot place the object between “inform” and “on.”
- Correct pattern: inform on + somebody
- Incorrect pattern: inform somebody on
How to Use “Inform on sb”?
You use “inform on sb” when you want to say someone has told authorities about another person’s secret or illegal actions. It is often used in formal or serious contexts, such as police reports or workplace situations involving rule-breaking. For example, you can say, “He informed on his colleague for stealing.”
Examples
Imagine a situation where a neighbor reports suspicious activity to the police. You could say:
- “She informed on her neighbor after seeing him break the law.”
- “The employee informed on the company’s illegal practices.”
- “He was afraid to inform on his friends, but he had to.”
- “Inform on sb in a sentence: The witness informed on the suspect to the police.”
Common Mistakes
People sometimes confuse the word order or use the wrong preposition. Here are some examples:
- Incorrect: I informed my teacher on the student.
- Correct: I informed on the student.
- Incorrect: She informed the police on her friend.
- Correct: She informed on her friend to the police.
Remember, you always say “inform on somebody,” not “inform somebody on.”
Differences / Synonyms
“Inform on sb” is similar to phrases like “report on sb” or “tell on sb,” but there are differences:
- Report on sb: Can mean giving information or feedback about someone, not always negative.
- Tell on sb: More informal and often used by children, meaning to tell an adult about someone’s bad behavior.
- Inform on sb: More formal and usually means giving information to authorities about secret or illegal actions.
Common Collocations
When using “inform on sb,” certain words often appear together:
- Inform on a suspect: Reporting a person suspected of a crime
- Inform on a colleague: Reporting a coworker’s wrongdoing
- Inform on a friend: Telling authorities about a friend’s illegal actions
- Inform on crime: Providing information about criminal activity
Real-life Dialogue
Here is a short conversation using “inform on sb”:
Anna: Did you hear that John informed on Mark for cheating?
Ben: Really? I didn’t expect that. I guess he wanted to do the right thing.
Anna: Yes, sometimes you have to inform on sb to keep things fair.
Practice
Complete the sentences with the correct form of “inform on”:
- She decided to _______ her coworker for breaking the rules.
- The witness _______ the suspect to the police last night.
- It’s hard to _______ a friend, but sometimes necessary.
FAQs
- What does “inform on sb” mean? It means to report someone’s secret or illegal actions to authorities.
- Is “inform on sb” formal or informal? It is generally formal and used in serious contexts.
- Can I say “inform somebody on”? No, the correct phrase is “inform on somebody.”
- Is “inform on sb” the same as “tell on sb”? Not exactly; “tell on sb” is informal and often used by children, while “inform on sb” is more formal.
- Who do you inform on sb to? Usually to police, authorities, or people in charge.

