Infinitives

Definition

Generally, an infinitive can be identified as:

• A full infinitive or to-infinitive
• A bare infinitive

The to-infinitive consists of two words including the preposition or particle to and the base form of a verb. It functions as a noun, an adjective, or an adverb in a sentence. On the other hand, the bare infinitive only includes a single word, the base form of a verb, it is used with auxiliary verbs, for example, to create interrogative and negative forms, to express future tense, or to introduce modality.

Example

1. Anna likes to eat lunch with her husband at the restaurant every weekend.
2. Alex can help his grandmother to get in his car.

In these examples, to eat is a full infinitive while help is a bare infinitive.

Using infinitives as nouns

An infinitive can function as a noun in a sentence in which it can be used as:

• A subject
• A direct object
• An object complement
• A subject complement

Example

1. To organize a campaign in the remote areas for increasing the citizens' awareness about their rights to live a good life is a noble initiative. (subject)
2. To spend few days in rural areas helps people to relax. (subject)
3. Hannah likes to stand by the ocean and look at the horizon. (direct object)
4. Anna is trying to convince his father to bring her a guitar. (direct object)
5. He doesn't expect her to be sad as long as he has bought her the car she likes. (object complement)
6. She begged him to marry her. (object complement)
7. Justice is to treat people equally. (subject complement)
8. The best way to face fear is to practice sport. (subject complement)

Notes :

• An object complement is a word or group of words that follows a direct object to describe or rename it.
• A subject complement is a word or set of words which follows the linking verbs to describe or rename a subject.

Using infinitives as adjectives

An infinitive can act as an adjective to describe a noun or pronoun that it follows.

Example

1. The best way to master electrical schemes is to practice them in concrete situations.
2. These are the five recommendations to change your wrong conduct of using internet.

In the first example, the infinitive phrase gives information about the noun 'way'. It introduces which way the sentence is talking about.

In the second example, the infinitive phrase gives information about the noun 'recommendations'. It introduces which five recommendations the sentence is talking about.

Using infinitives as adverbs

An infinitive can function as an adverb to modify a verb.

Example 

1. Olivia and Emma are working every Saturday and Sunday to save their needs at the university.
2. They have moved to another country to look for a good life.

In the first sentence, the infinitive phrase modifies the main verb 'working'. It shows why Olivia and Emma are working.

In the second sentence, the infinitive phrase modifies the ordinary verb 'moved'. It shows why they have moved.

Using infinitives with auxiliary verbs

The bare infinitive, the base form of a verb, can also be used in conjunction with  the auxiliary verbs to introduce:

• Interrogative sentences
• Negative sentences
• Simple future tense
• Modality

Example

1. Did Serena travel to California?
2. Does John drive to Arizona?
3. Salma didn't work on Saturday.
4. David doesn't repair his bicycle.
5. Alex will paint his house.
6. Olivia will do her homework before dinner.
7. Hannah must finish the work by Thursday.
8. Emma and Katrina can draw good pictures.

Exercises

Exercise (1)

The to-infinitive can be used as:

1. Adjective
2. Adverb
3. Noun
4. 1,2&3

The full infinitive means:

1. The base form of a verb
2. The base form of a verb preceded by at
3. The base form of a verb preceded by to

The bare infinitive means:

1. The infinitive with the particle to
2. The infinitive with the preposition by
3. The infinitive without the preposition to

Exercise (2)

Identify the full and bare infinitives in the following sentences:

1. Alex is helping me repair my car.
2. The athletes make a great effort to achieve their objectives. 
3. Steven should follow another method of nutrition to shape up his body properly.
4. May you open the door?
5. She felt him touch her hand.
6. Why study when they know the material by heart?
7. She is very happy to see her mother again.

Answer key

Exercise (1)

4

3

3

Exercise (2)

Full infinitives: to achieve, to shape up, to see

Bare infinitives: repair, follow, open, touch, study