Gerunds vs. Infinitives: The difference and when to use them

Gerunds and infinitives both transform verbs into other parts of speech, but they differ in form, function, and usage. Choosing between them depends on grammatical rules, the verb they follow, and sometimes the intended meaning. This post will help you make a little sense of when to use a gerund such as “walking” and when to use an infinitive such as “to walk”.

The difference

These words differ in form, function, and feel.

1. Form:
   • Gerund: Verb + “-ing” (e.g., running, singing, writing).
   • Infinitive: “To” + base verb (e.g., to run, to sing, to write), or bare infinitive (e.g., run, sing) after certain verbs.
2. Function:
   • Gerund: Always acts as a noun.
     • Example: Swimming is fun. (Subject)
   • Infinitive: Can act as a noun, adjective, or adverb.
     • Noun: I want to dance. (Object)
     • Adjective: A book to read. (Modifies “book”)
     • Adverb: I came to help. (Modifies “came”)
3. Feel:
   • Gerunds often emphasize the action itself or a general activity.
   • Infinitives often imply purpose, intention, or a specific future action.

When to use them

The choice between gerunds and infinitives depends on sentence structure, specific verbs, prepositions, and meaning. Here’s how to decide:

1. After specific verbs

Certain verbs dictate whether a gerund or infinitive follows:

• Verbs followed by gerunds:
  • Examples: enjoy, avoid, admit, consider, suggest, mind, keep, quit.
  • Rule: Use a gerund as the object.
    • Correct: I enjoy reading. / She avoided answering.
    • Incorrect: I enjoy to read. / She avoided to answer.
• Verbs followed by infinitives:
  • Examples: want, decide, hope, plan, promise, agree, refuse, learn.
  • Rule: Use an infinitive as the object.
    • Correct: I want to leave. / He decided to stay.
    • Incorrect: I want leaving. / He decided staying.
• Verbs followed by bare infinitives:
  • Examples: make, let, help (optional “to”), modals (can, must, should).
  • Rule: Use the base verb without “to.”
    • Correct: She made him laugh. / I can go.
    • Incorrect: She made him to laugh. / I can to go.
• Verbs that take either (Meaning changes):
  • Stop:
    • Gerund: Stop smoking = Quit the habit.
    • Infinitive: Stop to smoke = Pause to do it.
  • Remember:
    • Gerund: Remember locking = Recall doing it.
    • Infinitive: Remember to lock = Don’t forget to do it.
  • Try:
    • Gerund: Try stretching = Experiment with it.
    • Infinitive: Try to stretch = Attempt it.

2. After prepositions

• Gerund: Always use after a preposition (e.g., in, on, for, about, of).
  • Example: She’s good at singing. / He apologized for being late.
  • Incorrect: She’s good at to sing.
• Infinitive: Never follows a preposition directly, but can follow phrases like “in order to.”
  • Example: I came in order to help.

3. As the subject

• Gerund: Common for general activities or abstract ideas.
  • Example: Running keeps me fit.
  • Feels natural and concise.
• Infinitive: More formal, often for specific goals or hypothetical actions.
  • Example: To run every day is my goal.
  • Sounds stiffer, less common in casual speech.

4. Expressing purpose

• Gerund: Doesn’t express purpose directly.
  • Example: Swimming is relaxing. (Focus on the activity)
• Infinitive: Used to show why something is done.
  • Example: I exercise to stay healthy. (Purpose)

5. After adjectives

• Gerund: Rare after adjectives, except in fixed phrases (e.g., “worth doing“).
  • Example: This book is worth reading.
• Infinitive: Common after adjectives to describe ability, willingness, or extent.
  • Example: It’s hard to believe. / She’s eager to start.

6. In fixed expressions

• Some phrases lock in one form:
  • Gerund: No use crying over spilt milk.
  • Infinitive: To tell you the truth.

Key differences in meaning

Even when a verb allows both, the choice shifts the nuance:

• Like:
  • Gerund: I like cooking. (Enjoy the activity generally)
  • Infinitive: I like to cook. (Choose to do it, more specific)
• Forget:
  • Gerund: I forgot calling her. (Forgot the past action)
  • Infinitive: I forgot to call her. (Didn’t do it)

Quick tips

• Gerund: Think “the action as a thing.” Use after prepositions, as subjects, or with verbs about feelings/processes (enjoy, avoid).
• Infinitive: Think “purpose or potential.” Use for goals, intentions, or with verbs about decisions (want, plan).
• Check the Verb: Many verbs have fixed rules—memorize the big ones!
• Context: If meaning changes (e.g., stop, try), pick what fits your intent.

Examples in action

• Gerund: Writing emails takes time. / I avoid rushing. / Walking dogs is great exercise.
• Infinitive: I need to write an email. / He plans to rush. / I have to walk the dogs before I leave.