Introduction
One of the most confusing parts of English grammar is knowing when to use a gerund (verb + -ing) and when to use an infinitive (to + verb). Even advanced learners sometimes hesitate. But here is the good news: with a few clear rules and lots of practice, you can master this topic. This guide will help you understand the difference, avoid common errors, and use both forms naturally.
What Is a Gerund and What Is an Infinitive?
A gerund is the -ing form of a verb used as a noun. For example: swimming, reading, cooking. A gerund can be the subject or object of a sentence: Swimming is fun (subject) and I enjoy swimming (object).
An infinitive is the base form of a verb with to in front of it. For example: to swim, to read, to cook. Infinitives can also act as nouns, adjectives, or adverbs: I want to swim (object) or He has a book to read (adjective).
Rules: When to Use Gerund or Infinitive
- Use a gerund after certain verbs. Common verbs that take a gerund include: enjoy, avoid, suggest, finish, mind, consider, practice, recommend, admit, deny. Example: She suggested going to the park.
- Use an infinitive after certain verbs. Common verbs that take an infinitive include: want, hope, decide, plan, promise, learn, need, agree, refuse, offer. Example: They plan to visit London.
- Some verbs can take both, but the meaning changes. For example: remember + gerund means recall a past action (I remember locking the door), while remember + infinitive means not forget to do something (I remembered to lock the door). Other such verbs: stop, try, forget, regret.
- Use a gerund after prepositions. Any time you have a preposition (in, on, at, for, about, without, etc.), the verb that follows must be a gerund. Example: He is good at playing guitar.
- Use an infinitive after adjectives. When an adjective describes a feeling or quality, the next verb is often an infinitive. Example: I am happy to help you. It is important to study.
- Use a gerund as the subject of a sentence. Gerunds sound more natural as subjects than infinitives. Example: Traveling broadens your mind. (Compare: To travel broadens your mind – grammatically correct but less common.)
- Use an infinitive to express purpose. When you say why you do something, use an infinitive. Example: I went to the store to buy milk.
How to Use Gerund and Infinitive Correctly
Follow these steps to choose the right form every time:
- Identify the main verb. Look at the verb that comes before the blank. Is it one of the gerund-only verbs (like enjoy, avoid)? If yes, use the gerund.
- Check for a preposition. If there is a preposition immediately before the verb, you must use a gerund. For example: interested in, worried about, tired of.
- Ask: does the meaning change? For verbs like remember, forget, stop, try, think about the meaning. If you are talking about a past memory, use gerund. If you are talking about a future action or something you need to do, use infinitive.
- Test with a purpose question. If you can answer “Why?” with the verb, use an infinitive. Example: Why did you call? – To invite you.
- Practice common patterns. Make flashcards for the most frequent verbs. For example: want + to do, enjoy + doing, suggest + doing, decide + to do.
Examples in Sentences
- I enjoy swimming in the ocean.
- She wants to learn Spanish.
- They avoid eating junk food.
- He promised to call me later.
- We finished cleaning the house.
- I hope to travel to Japan next year.
- She is good at painting landscapes.
- He remembered to lock the door before leaving.
- I regret saying that to my friend.
- They stopped smoking for health reasons.
- She tried to open the jar, but it was stuck.
- We are excited to meet you.
- He suggested taking a break.
- I can’t afford to buy a new car right now.
- She spent the evening reading a novel.
Common Mistakes
- Mistake 1: ❌ I enjoy to play tennis.
✅ I enjoy playing tennis. - Mistake 2: ❌ She wants going to the party.
✅ She wants to go to the party. - Mistake 3: ❌ He is interested to learn French.
✅ He is interested in learning French. (Preposition in requires gerund.) - Mistake 4: ❌ I stopped to smoke last year. (Meaning: I stopped in order to smoke.)
✅ I stopped smoking last year. (Meaning: I quit the habit.) - Mistake 5: ❌ It is important studying for the exam.
✅ It is important to study for the exam. (After adjective important, use infinitive.)
Quick Summary
- Gerund = verb + -ing used as a noun. Use after certain verbs (enjoy, avoid, suggest), after prepositions, and as a subject.
- Infinitive = to + base verb. Use after certain verbs (want, hope, decide), after adjectives, and to express purpose.
- Meaning-changing verbs: remember, forget, stop, try, regret – choose based on context.
- Preposition rule: Always use gerund after a preposition.
- Subject rule: Gerund as subject sounds more natural (Running is healthy vs. To run is healthy).
Practice Exercises
Fill in the blanks with the correct form of the verb in parentheses: gerund or infinitive.
- She avoids _______ (eat) too much sugar.
- They decided _______ (move) to a new city.
- I am looking forward to _______ (see) you next week.
- He forgot _______ (bring) his homework to class.
- We enjoy _______ (spend) time with our family.
Answers:
- eating
- to move
- seeing
- to bring
- spending
Conclusion
Mastering gerunds and infinitives takes time, but with these rules and practice, you will make fewer mistakes. Remember to check the main verb, watch for prepositions, and pay attention to meaning-changing verbs. Keep practicing, and soon using the correct form will feel natural. Good luck!
FAQ
1. Can a gerund and an infinitive be used interchangeably?
Sometimes yes, but often no. With verbs like like, love, hate, start, begin, both forms are possible with little or no change in meaning. For example: I like swimming and I like to swim are both correct. However, with verbs like remember, forget, stop, try, the meaning changes, so you cannot swap them freely.
2. Why do we use a gerund after prepositions?
In English, a preposition must be followed by a noun or a noun-like form. A gerund functions as a noun, so it fits naturally after prepositions. An infinitive is not a noun form and cannot follow a preposition. For example: He is tired of working (not of to work).
3. What is the difference between “stop smoking” and “stop to smoke”?
This is a classic example of a meaning change. Stop smoking means you quit the habit (gerund = the action you stop). Stop to smoke means you pause another activity in order to smoke (infinitive = purpose). So: I stopped smoking last year (I no longer smoke). I stopped to smoke a cigarette (I paused walking/driving to have a cigarette).
4. Can an infinitive be the subject of a sentence?
Yes, but it is less common and often sounds formal or old-fashioned. For example: To err is human is correct but formal. In everyday English, we prefer the gerund as the subject: Making mistakes is human. However, when using an infinitive as a subject, it is often introduced by it as a dummy subject: It is important to study (not To study is important in casual speech).