00 / Non-finite Verbs
Preposition + -ing
In English, when a verb follows a preposition, it must take the -ing form (the gerund). This rule applies to all prepositions, including those following adjectives, nouns, or other verbs.
B1Intermediate
01 / Overview
When we want to use an action after a preposition, we cannot use the infinitive. Instead, we use the -ing form. This structure is common after adjectives with fixed prepositions, such as good at or afraid of, and after verbs like think about or apologize for.
02 / Form
Preposition + (not) + verb-ing
The preposition is followed immediately by the gerund. If there is a negative, not comes before the -ing form.
03 / Examples
04 / Common mistakes
I am interested in to learn Japanese.
I am interested in learning Japanese.
Always use the -ing form after a preposition, never the 'to' infinitive.
Thank you for help me.
Thank you for helping me.
Even short, common prepositions like 'for' require the gerund form of the following verb.
05 / To as a Preposition vs. To as an Infinitive
Be careful with the word to. If to is a preposition (like in look forward to or object to), it must be followed by -ing.
| Usage | Example |
|---|---|
| To as part of an infinitive | I want to eat. |
| To as a preposition | I look forward to meeting you. |
06 / Practice
He is afraid of (fly) in small planes.
Show answer
Answer: flying
Why: The preposition 'of' must be followed by the -ing form of the verb.
Thank you for (not / make) too much noise.
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Answer: not making
Why: When making the gerund negative, place 'not' directly before the -ing form.
We are looking forward to (see) you again.
Show answer
Answer: seeing
Why: In the phrase 'look forward to', 'to' is a preposition, so it requires the -ing form.