Grammar: Infinitive vs -ing Form
Learn how to avoid grammar errors with the infinitive vs -ing form.
Look at the example errors below. Can you fix them?
|– The Federal Reserve agreed
|– The teacher gave the students a test
What are the grammar rules?
1. Verbs can have different forms. There are many rules, but we’ll focus on the most common errors with the infinitive (e.g. think) and the -ing form (e.g. thinking).
2. We use the infinitive (without to) after the auxiliary verbs do and did, as well as after modal verbs such as should, can and would.
– Do you think our paper will be published?
– More research should be conducted.
– This may lead to an increase in crime.
3. We also use the infinitive (with to) to express purpose.
– Professor Dupont came here to study frogs.
– To begin the test, press the Enter key.
4. We use the -ing form as the subject or object of a verb.
– Conducting research is very enjoyable.
– I dislike supervising PhD candidates.
5. We also use the -ing form after propositions such as in, on, at and about.
– He’s good at writing.
– The government had a discussion about increasing immigration.
6. After some verbs, we use the infinitive (usually with to). We use the -ing form after other verbs.
|– I’m trying ||– I’m trying to learn Chinese.|
|– I enjoy ||– I enjoy studying at university.|
7. When you learn a new verb, make it a habit to write down the verb pattern and an example. A good learner’s dictionary will usually give you this information.
promise to do sth.
e.g. She promised to help her brother with this homework.
Here’s a short list to get you started:
|Verb + infinitive (with to)||Verb + -ing form|
|afford to do sth.||admit doing sth.|
|manage to do sth.||enjoy doing sth.|
|promise to do sth.||give up doing sth.|
|prefer to do sth.||involve doing sth.|
|hope to do sth.||put off doing sth.|
8. Some verbs, most notably make, let, see and hear, are followed by an infinitive without to.
– The teacher made us do our homework.
– Professor Zheng let us go home early.
– I saw him cheat during the exam.
Here are the corrected errors from the start of the lesson.
|– The Federal Reserve agreed ||– The Federal Reserve agreed to raise interest rates.|
|– ||– Recruiting study participants can be very challenging.|
|– The teacher gave the students a test ||– The teacher gave the students a test to check their understanding.|
Complete each sentence using the correct form of the verb in brackets. If you use an infinitive, remember that you may need to use to.