The Core Difference
- Gerund: A verb ending in -ing that functions as a noun.
- Swimming is fun.
- Infinitive: The base form of a verb, usually with to (full infinitive). It can function as a noun, adjective, or adverb.
- I want to swim.
When to Use the Gerund (-ing form)
| 1. As the Subject of a Sentence | Smoking is bad for your health. Learning a new language takes time. |
| 2. After Prepositions | Thank you for helping me. She left without saying goodbye. I’m interested in learning Japanese. |
| 3. After Certain Verbs | I enjoy reading novels. He finished working at 6 PM. Do you mind opening the window? She suggested going to a movie. You should avoid eating late at night. We are considering moving to Canada. He practices playing piano every day. |
| 4. After Certain Phrases | It’s no use / It’s no good crying over spilt milk. I can’t help laughing at his jokes. I can’t stand waiting in long lines. |
When to Use the Infinitive (to + verb)
| 1. To Express Purpose (Why you do something) | I went to the store to buy milk. (Purpose = buy milk) She is studying to become a doctor. |
| 2. After Adjectives | It’s easy to learn Spanish pronunciation. I’m happy to see you. This book is hard to understand. |
| 3. After Certain Verbs | I want to eat pizza. You need to sleep more. They decided to sell their car. We hope to visit Paris someday. He learned to drive last year. I promise to call you later. She plans to start a business. |
| 4. After Question Words (except Why) | I don’t know what to do. Tell me how to get to the station. We learned where to find cheap flights. |
Verbs that Change Meaning
Some verbs can be followed by both a gerund and an infinitive, but the meaning changes.
| Verb | Gerund (ing) | Infinitive (to) |
|---|---|---|
| stop | Stop smoking = quit the habit | Stop to smoke = pause in order to smoke |
| remember | Remember locking the door = you have a memory of doing it | Remember to lock the door = don’t forget to do it in the future |
| forget | I’ll never forget meeting her = memory of past event | Don’t forget to meet her = reminder for future action |
| try | Try pressing F5 = experiment to see if it works | Try to press F5 = attempt, but might fail |
| regret | I regret telling him = sorry about past action | I regret to tell you = sorry about the news you will give |
Common Mistakes to Avoid
| ❌ Incorrect | ✅ Correct | Rule |
|---|---|---|
| I enjoy to read. | I enjoy reading. | After enjoy, use gerund. |
| She suggested to go out. | She suggested going out. | After suggest, use gerund. |
| I want going home. | I want to go home. | After want, use infinitive. |
| It’s important studying. | It’s important to study. | After it is + adjective, use infinitive. |
| I’m good to swim. | I’m good at swimming. | After preposition (at), use gerund. |
Quick Summary Cheat Sheet
| Rule | Use Gerund (-ing) | Use Infinitive (to + verb) |
|---|---|---|
| Subject of sentence | ✓ Cooking is relaxing. | ❌ |
| After prepositions | ✓ Thanks for helping. | ❌ |
| To express purpose | ❌ | ✓ I came to help. |
| After adjectives | ❌ | ✓ It’s easy to do. |
| After certain verbs | enjoy, finish, mind, suggest, avoid | want, need, decide, hope, promise, plan |
