If you’ve ever found yourself second-guessing whether it’s interested in or interested on, you’re not alone.
Prepositions in English can be deceptively tricky, and small words often have a big impact on clarity.
In this guide, we’ll explore the correct usage of “interested” with prepositions, explain why “in” is the right choice, and uncover the grammar rules and nuances behind this everyday phrase.
“Interested in” is the correct phrase in English, while “interested on” is grammatically incorrect and should be avoided.
Exploring the Adjective ‘Interested’
The word interested functions as an adjective. It describes a person’s curiosity, engagement, or attraction toward a subject, topic, or activity.
You might say, “She’s interested in art” or “I’m interested in learning French.” But would you ever say “interested on music”? Likely not—and there’s a reason for that.
Example Sentences:
- ✅ I’m interested in modern architecture.
- ❌ I’m interested on modern architecture.
The difference comes down to grammar and prepositional compatibility, which we’ll explore in depth below.
Common Richly Diverse Contexts
“Interested in” appears across multiple areas of life, from academics and business to personal hobbies and emotional connections.
Contexts Where ‘Interested In’ is Common:
- Career & Education:
“He’s interested in pursuing a degree in economics.” - Relationships:
“Are you interested in anyone right now?” - Hobbies & Entertainment:
“They’re interested in painting and photography.” - Technology & Business:
“Investors are interested in the new startup’s growth.”
These examples highlight that “interested in” isn’t just grammatically correct—it’s the natural and widely accepted phrase in English.
Usage with Gerunds
Gerunds (verbs ending in -ing used as nouns) commonly follow “interested in.”
Examples:
- “She’s interested in traveling the world.”
- “I’m interested in learning Spanish.”
- “They’re interested in volunteering abroad.”
This structure—interested + in + gerund—is not only grammatically correct but also idiomatic English.
💡 Tip: If you’re using an activity after “interested,” make sure it’s in gerund form (e.g., swimming, reading, writing).
Prepositions in the English Language: A Brief Overview
To truly understand why we say interested in rather than interested on, it helps to review what prepositions are and how they function in English.
What Are Prepositions?
Prepositions are linking words that show the relationship between a noun (or pronoun) and other parts of the sentence. They often answer the questions: where, when, how, and why.
Common Prepositions:
- in
- on
- at
- by
- with
- for
- from
- about
Each preposition has its own function and governs the meaning of the sentence.
How Prepositions Connect Ideas
Prepositions establish connections, such as:
- Location: “The book is on the table.”
- Time: “I’ll call you at 6 p.m.”
- Direction: “He walked into the room.”
- Cause/Reason: “She died from exhaustion.”
In the case of interested, the preposition you choose determines how that interest is interpreted.
The Specific Roles of ‘In’ Within Prepositions
The preposition in is used to indicate:
- Involvement or Participation: “He’s involved in charity work.”
- State or Condition: “She’s in trouble.”
- Interest or Focus: “I’m interested in photography.”
So when we say “interested in,” we’re showing that someone is engaged with or focused on a subject. It fits the grammatical and semantic structure of English perfectly.
The Case for ‘Interested In’: Usage and Grammar
Let’s dive deeper into why interested in is the correct structure.
Why “Interested On” is Incorrect:
The preposition on generally refers to surfaces or positions:
- “The phone is on the desk.”
- “I saw it on TV.”
It does not convey emotional engagement or curiosity. Using interested on breaks the natural link between adjective and preposition.
Grammar Rule:
Adjective + Preposition Collocation
Certain adjectives naturally pair with specific prepositions. This is called collocation, and it’s more about convention than strict logic.
Other Common Collocations:
| Adjective | Correct Preposition | Example |
|---|---|---|
| good | at | “She’s good at math.” |
| afraid | of | “He’s afraid of spiders.” |
| tired | of | “I’m tired of waiting.” |
| interested | in | “They’re interested in robotics.” |
Unpacking the Combination of ‘Interested’ and Prepositions
There are a few cases where “interested” appears with other prepositions, but these structures carry different meanings or are context-specific.
Examples:
- Interested to:
“I’m interested to hear your thoughts.”
(Used to express curiosity about receiving information.) - Interested by:
“I was interested by his speech.”
(Less common, often sounds more formal or academic.)
However, in most scenarios, especially when speaking about general interests, “interested in” is your go-to choice.
Understanding ‘Interested In’ vs. ‘Interested To’
Let’s compare interested in and interested to side-by-side for clarity:
| Phrase | Meaning |
|---|---|
| Interested in | You have curiosity or attraction toward something. |
| Interested to | You are eager or ready to receive new information or action. |
Examples:
- “I’m interested in baking.” (interest in a hobby)
- “I’m interested to know what happened.” (anticipation of new info)
Remember: interested to is often followed by verbs like hear, see, or know.
Common Errors and Misconceptions
Common Mistakes:
- ❌ “She’s interested on dancing.”
- ❌ “I’m interested to math.”
- ❌ “They’re interested by travel.”
Correct Forms:
- ✅ “She’s interested in dancing.”
- ✅ “I’m interested in math.”
- ✅ “They’re interested in travel.”
📌 Always check how native speakers use a phrase before adopting it. Tools like YouGlish or corpora like COCA can help.
Practical Tips for Mastering Prepositional Phrases
Mastering prepositions—especially those that follow adjectives like interested—takes time, but it’s easier with consistent exposure and practice.
Tips to Remember:
- Read Frequently: Notice how adjectives and prepositions appear in context.
- Use Flashcards: Create cards with common adjective-preposition pairs.
- Listen to Native Speakers: Pay attention to natural usage in TV shows, podcasts, and movies.
- Practice Writing Sentences: Try forming five original sentences with “interested in.”
❓ 6 FAQs
Is it correct to say “interested on”?
No, “interested on” is grammatically incorrect. The correct phrase is “interested in.”
Why do we say “interested in”?
“In” is the proper preposition that shows emotional or intellectual engagement with a topic.
What’s the structure after ‘interested in’?
Typically: interested in + noun or gerund (e.g., painting, learning, technology).
Can I say “interested to”?
Yes, but only in specific cases, such as “interested to hear” or “interested to know,” where you’re expressing anticipation.
Is “interested by” correct?
It’s rare and mostly formal, meaning something caused your interest. Example: “He was interested by the presentation.”
How do I avoid common prepositional mistakes?
Learn adjective-preposition collocations (e.g., good at, afraid of, interested in) and expose yourself to native content regularly.
Final Thoughts
The verdict is clear: “interested in” is the correct and natural usage in English. While interested to and interested by have niche roles, interested on is almost always incorrect.
Understanding how adjectives pair with prepositions enhances not just your grammar but also the clarity and effectiveness of your communication.
So next time you’re tempted to say interested on, remember—English doesn’t just favor interested in… it expects it.
