Gerunds and Infinitives

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.

2. Infinitives are 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.

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.

Examples:

• He enjoys swimming. "Enjoy" requires a gerund.
• He wants to swim. "Want" requires an infinitive.

5. Some verbs are followed by gerunds as objects.

Examples:

• She suggested going to a movie.
• Mary keeps talking about her problems.

6. Some verbs are followed by infinitives.

Examples:

• She wants to go to a movie.
• Mary needs to talk about her problems.

http://wwwedu.ge.ch/cptic/prospective/projets/anglais/exercises/gerund1.htm