What Does “Warn sb off sth” Mean?
“Warn sb off sth” means to advise or tell someone not to do something or to stay away from a particular thing or place because it may be dangerous or harmful.
Introduction
The phrasal verb “warn sb off sth” is commonly used in English to express a warning given to someone about avoiding a certain action, place, or thing. It often implies a strong caution because of possible risk or trouble. Understanding the Warn sb off sth meaning helps learners communicate warnings clearly and naturally. This phrase is useful in everyday situations, from informal conversations to formal advice.
Quick Info Box
- Phrasal verb: Warn somebody off something
- Type: Transitive
- Level: B2 (Upper-Intermediate)
- Short meaning: To advise someone not to do something or to keep away from something
Structure (Grammar Rules)
“Warn sb off sth” is a separable transitive phrasal verb. The object (somebody) always comes immediately after “warn” and before “off.” The phrasal verb is followed by the object (something) which is the thing to avoid.
Patterns:
- Warn + somebody + off + something
- Example: They warned him off the dangerous area.
How to Use Warn sb off sth?
Use “warn sb off sth” when you want to tell someone to avoid a particular action, place, or thing because it could cause harm or trouble. It is often used in warnings related to safety, health, or legal issues.
It is commonly followed by a person (sb) and then the thing or place (sth) they should avoid.
Examples
Imagine a friend telling you to stay away from a risky neighborhood. They might say:
- “I warned him off going to that part of town at night.”
- “The doctor warned her off eating too much sugar.”
- “They warned us off investing in that company because it seemed suspicious.”
- “Parents often warn their children off talking to strangers.”
- “The signs warned hikers off the cliff edge.”
These examples show how “warn sb off sth” is used in real-life situations.
Common Mistakes
People sometimes confuse the word order or the objects in this phrasal verb. Here are some common errors:
- Incorrect: Warn off him the place.
- Correct: Warn him off the place.
- Incorrect: Warn somebody the danger off.
- Correct: Warn somebody off the danger.
Remember that “sb” always comes right after “warn,” and “off” follows the person, not before.
Differences / Synonyms
Similar phrasal verbs include “tell sb not to do sth” and “advise sb against sth.” However, “warn sb off sth” usually suggests a stronger caution, often related to safety or risk.
- Warn sb off sth: Strong advice to avoid due to danger.
- Advise sb against sth: Suggest not to do something, often politely.
- Tell sb not to do sth: Direct instruction or command.
Common Collocations
Here are common objects used with “warn sb off”:
- Warn sb off danger – advising to avoid harm
- Warn sb off places – cautioning to stay away from locations
- Warn sb off actions – advising not to do certain things
- Warn sb off substances – such as drugs, alcohol, or harmful foods
- Warn sb off investments – cautioning against financial risks
Related Phrasal Verbs
Here are related phrasal verbs of warn sb off sth:
Real-life Dialogue
Here is a short conversation using “warn sb off sth”:
Anna: I’m thinking about hiking near the old mine.
Ben: I would warn you off that area. It’s dangerous and not safe for visitors.
Anna: Thanks for the warning. I’ll choose a safer trail.
Practice
Fill in the blank with the correct form of “warn sb off sth”:
- The teacher __________ the students __________ cheating on the exam.
- Local authorities __________ residents __________ swimming after the storm.
- My parents always __________ me __________ staying out too late.
FAQ
- Q: Is “warn sb off sth” formal or informal?
A: It can be used in both formal and informal contexts. - Q: Can I use “warn sb off” without an object?
A: Usually, it needs an object (something to avoid). - Q: What is the difference between “warn sb off” and “warn sb about”?
A: “Warn sb off” advises avoiding something; “warn sb about” means informing of a potential problem. - Q: Is “warn sb off sth” separable?
A: Yes, but the person (sb) must stay immediately after “warn.” - Q: Can I replace “sb” with a name?
A: Yes, for example, “warn John off the area.”

