In my years of teaching English and guiding students through tricky grammar lessons, I’ve often seen confusion arise around the preposition in the phrase “Interested In or Interested On: What’s the Correct Preposition to Use?“. In the classroom, small mistakes in speaking or writing can create doubt, but with steady practice, useful examples, and repetition, learners gradually start recognizing correct usage naturally.
While correcting essays or listening to conversations, I noticed awkward expressions and poor choices in phrases, which often stem from a lack of building understanding of the rule. Following real-life patterns, exposure, and forming a habit helps technology, discussion, and sentence construction become more polished, clear, and smooth, flowing with ease in any context.
When teaching prepositions, I stress that hesitation in a line or sentence is normal. Over time, consistent teaching, practice, and awareness of phrase structure strengthens confidence and fluency. Correct English prepositions can be tricky, but focusing on curiosity, involvement, and focus on science or academic topics helps learners express ideas grammatically and accurately.
Avoiding unnatural forms like Interested On, understanding syntax, usage, and prepositional nuances, and using spoken or formal style appropriately improves communication, clarity, language mastery, and linguistic skill. A smooth flow, consistent academic or casual expression, and conscious structure allow learners to confidently express ideas without awkwardness or errors, turning grammar challenges into a natural habit.
Understanding the Adjective ‘Interested’
The adjective interested describes someone who is eager, curious, or engaged in something. It focuses on the person’s feelings or attention rather than the object itself.
- Correct Usage Examples:
- “She’s interested in digital marketing.”
- “He is interested in volunteering at the local shelter.”
- Incorrect Usage Example:
- “She’s interested on digital marketing.”
It is important to note the difference between interested and interesting:
- Interested = having curiosity or concern about something.
- Interesting = something that captures attention or arouses curiosity.
Examples:
- Correct: “I’m interested in psychology.”
- Correct: “This book is interesting.”
- Incorrect: “I’m interesting in psychology.”
Understanding this distinction helps you use prepositions accurately and avoid confusing your readers.
The Role of Prepositions in English
Prepositions are small but powerful words that link nouns, pronouns, or phrases to other words in a sentence. They indicate direction, location, time, cause, and relationship. Choosing the wrong preposition can subtly—or drastically—change meaning.
Examples of preposition misuse:
- Incorrect: “She is good on math.”
- Correct: “She is good at math.”
Prepositions like in, on, at, for, to, with appear frequently with adjectives. Certain adjectives, like interested, follow specific prepositional patterns, and breaking these rules can make even well-written sentences sound unnatural.
Why ‘Interested In’ is Correct
The combination “interested in” is standard in English. “In” connects the person’s interest to a noun or gerund that represents an activity or topic.
Examples in various contexts:
- Academic: “She’s interested in quantum physics.”
- Professional: “He is interested in joining the research team.”
- Casual: “I’m interested in cooking Italian dishes.”
Comparison Table:
| Phrase | Example | Correctness |
| Interested in | “I’m interested in art history.” | ✅ Correct |
| Interested on | “I’m interested on art history.” | ❌ Incorrect |
| Interested to | “I’m interested to hear your opinion.” | ✅ Correct in limited cases |
Using interested on is almost always incorrect in standard English. Even in informal contexts, it sounds awkward and ungrammatical.
Common Confusions: ‘Interested To’ vs. ‘Interested In’
While “interested in” connects to nouns or gerunds, “interested to” is sometimes correct before verbs in the infinitive form. It expresses curiosity about performing or learning something new.
Examples:
- Correct: “I’m interested to learn more about renewable energy.”
- Correct: “She’s interested to see how the experiment works.”
- Incorrect: “I’m interested to cooking Italian dishes.”
Side-by-Side Comparison Table:
| Phrase | When to Use | Example |
| Interested in | Nouns or gerunds | “He’s interested in painting.” |
| Interested to | Infinitive verbs (formal) | “She’s interested to attend the conference.” |
| Interested on | ❌ Avoid | “He’s interested on learning.” ❌ |
Understanding the subtle difference ensures your writing stays professional and precise, which is particularly important in academic papers, reports, and emails.
Usage with Gerunds and Nouns
The phrase “interested in” works seamlessly with both gerunds (verbs ending in -ing) and nouns.
Examples with Gerunds:
- “She’s interested in studying neuroscience.”
- “They are interested in volunteering for community service.”
Examples with Nouns:
- “He is interested in artificial intelligence.”
- “The students are interested in environmental science.”
Notice how “interested on” never fits naturally with gerunds or nouns. Using the wrong preposition can make the sentence sound uneducated or awkward.
Practical Tips for Mastering ‘Interested In’
Here are actionable strategies to help you master prepositions with interested:
- Tip 1: Always check if the following word is a noun or gerund. If yes, use in.
- Tip 2: For infinitive verbs, formal constructions can use interested to.
- Tip 3: Read aloud to identify unnatural phrasing. If it sounds off, check the preposition.
- Tip 4: Practice by rewriting incorrect sentences.
- Tip 5: Observe native English texts, emails, and articles for natural usage.
Practice Table:
| Incorrect | Correct | Notes |
| I’m interested on learning Spanish. | I’m interested in learning Spanish. | Always use in with gerunds |
| She’s interested to cooking. | She’s interested in cooking. | Infinitive verbs require “to” but not in gerund form |
| They’re interested on digital marketing. | They’re interested in digital marketing. | “On” is almost always wrong |
These exercises can help students, teachers, and professionals internalize correct prepositional patterns.
Common Mistakes and How to Avoid Them
Even advanced English speakers occasionally misuse interested in/on/to. Here’s a list of frequent mistakes:
- Using on instead of in with gerunds/nouns.
- Using to with nouns: “I’m interested to history.”
- Confusing interested in with keen on (more common in British English).
- Forgetting to adjust prepositions in formal writing.
Tips to avoid mistakes:
- Always pair interested with the correct grammatical structure.
- Use checklists before submitting academic or professional writing.
- Incorporate real-life examples to reinforce memory.
Extended Insights for Professionals and Teachers
For professionals, incorrect preposition usage can affect credibility:
- Emails: “I’m interested on joining your team” can reduce perceived professionalism.
- Reports: Misused prepositions may confuse readers or stakeholders.
For teachers, emphasizing patterns rather than rules helps students:
- Focus on examples and repetition instead of abstract definitions.
- Encourage students to create their own sentences for practice.
- Highlight the difference between formal and informal contexts.
Case Study:
A marketing intern submitted a report stating, “I’m interested on social media trends.” The manager corrected it to “interested in social media trends.” This small change made the sentence sound polished, professional, and credible.
Quick Reference Table
| Phrase | Correct Usage | Notes |
| Interested in | “I’m interested in learning French.” | Standard, widely accepted |
| Interested on | “I’m interested on learning French.” | ❌ Incorrect |
| Interested to | “I’m interested to hear your opinion.” | ✅ Limited correct use, formal tone |
This table serves as a handy reference for quick writing checks.
Conclusion
Understanding the difference between Interested In and Interested On is crucial for clear English communication. Learners often face confusion around prepositions, but with practice, exposure to real-life patterns, and repetition, recognizing correct usage becomes natural.
Using Interested In in spoken, formal, or academic contexts strengthens fluency, confidence, and grammatically correct expression, while avoiding unnatural forms like Interested On ensures clarity and polished communication. Developing this habit through consistent teaching, practice, and awareness of phrase structure turns a tricky grammar rule into a smooth, intuitive skill for everyday English.
FAQs
Q1: Is “Interested On” ever correct?
A1: No, in standard English, Interested On is considered unnatural. Use Interested In to express curiosity, focus, or involvement.
Q2: Can “Interested In” be used in formal writing?
A2: Yes, Interested In works in both formal and spoken contexts, making it a versatile choice for academic and professional settings.
Q3: How can learners remember this rule?
A3: Through consistent practice, exposure to real-life patterns, and repetition, learners can build a habit of correct usage and confidence.
Q4: What common mistakes should I avoid?
A4: Avoid using Interested On, mixing prepositions, or creating awkward expressions that disrupt the flow and clarity of communication.
Q5: Does practice really improve fluency?
A5: Absolutely. Steady practice, along with awareness of syntax, prepositional nuances, and phrase structure, strengthens fluency and linguistic skill naturally.
