A gerund is a verb that functions as noun. For example:
- I enjoy playing tennis. I enjoy play tennis" is incorrect.
- We practice speaking English every day.
- They just bought a new swimming pool.

In English the infinitive is made of to and the verb. For example:
- I want to learn a new language.
- You forgot to close the door.

Verbs are often followed by infinitives or gerunds and choosing which to use has few fixed rules, it depends mainly on the individual verb.

Here are some common verbs that can be followed by gerunds, but not infinitives.

admit - He admitted taking the money.
celebrate - We celebrated winning the competition.
deny - The government denied spending too little on education.
dislike - I dislike complaining.
enjoy - She enjoys meeting her friends.
finish - I finished working there last month.
imagine - I imagine being a waitress is a difficult job.
keep - Where are my keys? I keep losing them.
mind - I don't mind waiting, we've got time.
miss - I miss talking with my sisters.
remember - Do you remember going to Italy?
risk - Jeff's always late. He risks losing his job.
stop - Don't stop singing, it's really nice.
suggest - I suggest having lunch first.

Gerunds are also used after some phrasal verbs. For example:
- If you keep on doing the same thing, you'll get the same results.
- She wants to give up drinking coffee.

Below are some common verbs that can be followed by infinitives, but not usually gerunds.

aim - I'm aiming to finish this book by the end of March.
afford - I can't afford to buy new clothes.
agree - My boss agreed to give me a reference.
decide - We decided to have a baby.
deserve - You deserve to have a better score.
forget - Don't forget to lock the door.
hope - I hope to go to Harvard Business School.
learn - I learnt to read when I was 3 years old.
mean - I'm sorry, I didn't mean to make you angry.
need - You don't need to study a lot, you need to study a little for a long time.
offer - He offered to help me carry these bags.
plan - They plan to go abroad next year.
pretend - He's pretending to be sick.
promise - She promised to be here on time.
refuse - Why do they always refuse to listen?
seem - She seems to be really intelligent.

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