1. A gerund is a noun made from a verb by
adding "-ing." The gerund form of the verb "read" is "reading." You can
use a gerund as the subject, the complement, or the object of a
sentence.
Examples:
Reading helps you learn English. subject of sentence
Her favorite hobby is reading. complement of sentence
I enjoy reading. object of sentence
Gerunds can be made negative by adding "not."
Examples:
He enjoys not working.
The best thing for your health is not smoking.
What is an infinitive?
2. An infinitive is the "to" form of the
verb. The infinitive form of "learn" is "to learn." You can also use an
infinitive as the subject, the complement, or the object of a sentence.
Examples:
To learn is important. subject of sentence
The most important thing is to learn. complement of sentence
He wants to learn. object of sentence
Infinitives can be made negative by adding "not."
Examples:
I decided not to go.
The most important thing is not to give up.
Use a gerund or an infinitive?
3. Both gerunds and infinitives can be used
as the subject or the complement of a sentence. However, as subjects or
complements, gerunds usually sound more like normal, spoken English,
whereas infinitives sound more abstract. In the following sentences,
gerunds sound more natural and would be more common in everyday English.
Infinitives emphasize the possibility or potential for something and
sound more philosophical. If this sounds confusing, just remember that
90% of the time, you will use a gerund as the subject or complement of a
sentence.
Examples:
Learning is important. normal subject
To learn is important. abstract subject - less common
The most important thing is learning. normal complement
The most important thing is to learn. abstract complement - less common
4. As the object of a sentence, it is more
difficult to choose between a gerund or an infinitive. In such
situations, gerunds and infinitives are not normally interchangeable.
Usually, the main verb in the sentence determines whether you use a
gerund or an infinitive.