Infinitive

The infinitive is the base form of a verb, often preceded by the word "to." In English, infinitives are versatile and can function as nouns, adjectives, or adverbs.

Basic Formulation:

The infinitive form of a verb is the base form of the verb, unchanged by tense, aspect, or mood. It is often preceded by the word "to."

For example:

  • To walk, to eat, to sleep

Use as Nouns:

Infinitives can function as nouns in a sentence, serving as the subject, object, or complement of a verb.

For example:

  • To walk is good exercise. (Subject of the sentence)
  • She loves to dance. (Direct object of the verb)
  • His goal is to succeed. (Subject complement)

Use as Adjectives:

Infinitives can also function as adjectives, modifying nouns to provide additional information about them.

For example:

  • He is the man to trust. (Describing the man)
  • This is a book to read. (Describing the book)
  • She is a person to admire. (Describing the person)

Use as Adverbs:

Infinitives can function as adverbs, modifying verbs, adjectives, or other adverbs to provide information about manner, purpose, or result.

For example:

  • She ran to catch the bus. (Purpose - modifying the verb "ran")
  • The movie was too scary to watch. (Result - modifying the adjective "scary")
  • He walked quickly to avoid being late. (Purpose - modifying the adverb "quickly")

Split Infinitive:

In English, it's acceptable to place an adverb between "to" and the verb in an infinitive. This is known as a split infinitive.

For example:

  • He decided to quickly finish the task.
  • She wants to carefully consider her options.

Bare Infinitive:

In certain constructions, particularly after modal verbs (such as can, could, may, might, must, shall, should, will, would), the infinitive is used without "to." This is called the bare infinitive.

For example:

  • He can swim.
  • They should leave now.
  • I will help you.

Zero Infinitive:

Some verbs, particularly causative verbs like make, let, have, and help, can be followed by the base form of the verb without "to." This is called the zero infinitive.

For example:

  • She made him cry.
  • They let us go early.


Constructing infinitives in English is relatively straightforward. By following these guidelines, you can construct infinitives accurately in English sentences, allowing you to express intentions, desires, purposes, permissions, obligations, and more effectively. Here's how to do it:


Base Form of the Verb:
The infinitive form of a verb is the base form, which means it does not change to reflect tense, aspect, mood, or number. It is simply the verb in its most basic form.

To + Base Form:
In English, infinitives are often preceded by the particle "to." This is known as the "to-infinitive" form. However, not all infinitives are preceded by "to." There are also bare infinitives, which are used without "to" in certain constructions.

Usage After Verbs:
Infinitives are commonly used after certain verbs, such as:

  • Modal verbs: can, could, may, might, must, shall, should, will, would.
  • Verbs of perception: see, hear, watch, feel, etc.
  • Verbs expressing desire or intention: want, wish, hope, expect, etc.
  • Verbs expressing permission or obligation: allow, permit, require, etc.
  • Verbs expressing preference or intention: like, prefer, intend, plan, etc.

Usage After Adjectives and Nouns:
Infinitives can also be used after adjectives and nouns to express purpose, intention, result, or reason.

  • After adjectives: It is important to study regularly.
  • After nouns: She has the ability to speak multiple languages.

Bare Infinitives:
In some constructions, infinitives are used without the particle "to." These are called bare infinitives. Bare infinitives are used after certain verbs such as "make," "let," "help," "hear," "see," and "watch," as well as after modal verbs when followed by another verb.

Parallel Structures:
Infinitives are often used in parallel structures, where multiple verbs share the same "to" or "to not" particle.
Example: She likes to swim, to hike, and to bike.

Negative Infinitives:
To form negative infinitives, the word "not" is added before "to."
Example: She decided not to go to the party.

Split Infinitives:
In English, it is possible to split infinitives by placing an adverb between "to" and the base form of the verb. While this was traditionally discouraged, it is now widely accepted in modern English usage.
Example: She decided to quickly finish her work.


By mastering the usage of infinitives, we can enhance our ability to construct grammatically correct sentences, convey various meanings and intentions, and communicate effectively in both spoken and written English. Infinitives are fundamental to English grammar and are used in a wide range of contexts, making them essential for language learners to grasp. Understanding infinitives and their usage is crucial for several reasons:


Basic Sentence Structure: Infinitives form the base form of a verb and are essential for constructing sentences in English. They are used after certain verbs, adjectives, and nouns to complete the structure of a sentence.

Verb Patterns: Knowing how to use infinitives allows learners to recognize and use common verb patterns in English. For example, certain verbs are followed by infinitives, while others are followed by gerunds or bare infinitives.

Expressing Purpose: Infinitives are often used to express purpose or intention. By using infinitives, learners can convey why an action is being performed or what its intended outcome is.

After Modal Verbs: Infinitives are used after modal verbs (e.g., can, could, may, might, must, shall, should, will, would) to express various meanings such as ability, possibility, obligation, permission, and necessity.

Verbs of Perception: Infinitives are used after verbs of perception (e.g., see, hear, watch, feel) to express what someone observes or experiences.

Infinitive of Result: Infinitives can be used to express the result or consequence of an action, often after adjectives or nouns.

Infinitive of Reason: Infinitives can express the reason or cause for an action when used after adjectives or nouns.

Infinitive Clauses: Infinitive clauses are used to provide additional information about a verb, noun, or adjective in a sentence.

To + Infinitive: The structure "to + infinitive" is used to express purpose, intention, or result, and is commonly used in various contexts such as making plans, giving instructions, expressing preferences, or stating goals.

Parallel Structures: Infinitives are often used in parallel structures to maintain consistency and balance in sentences, especially in lists or series of actions.


Infinitive or Gerund?

Both infinitives and gerunds are forms of verbs that function as nouns in a sentence. However, they are used in different contexts:

Infinitive (to + base form of the verb):


Used after certain verbs:
Some verbs are followed directly by an infinitive, such as "want," "need," "decide," "promise," etc.
For example: "I want to learn." "She promised to help."


After adjectives:
Certain adjectives are followed by an infinitive, such as "happy," "eager," "excited," etc.
For example: "She was happy to see you."


After certain nouns:
Some nouns are followed by an infinitive, such as "opportunity," "decision," "ability," etc.
For example: "He has the ability to succeed."


In the structure "too + adjective/adverb + infinitive" and "enough + adjective/adverb + infinitive."
For example: "She is too tired to go on."


Gerund (base form of the verb + -ing):


As a subject:
Gerunds can function as the subject of a sentence.
For example: "Swimming is my favorite sport."


After prepositions:
Gerunds are often used after prepositions.
For example: "She is good at playing guitar."


After certain verbs:
Some verbs are followed directly by a gerund, such as "enjoy," "avoid," "consider," "admit," etc.
For example: "He enjoys swimming."


After certain expressions:
Some expressions are followed by a gerund, such as "It's no use," "It's worth," "Can't help," etc.
For example: "It's worth trying."


In summary, use infinitives after certain verbs, adjectives, nouns, and in certain structures like "too/enough + adjective/adverb + infinitive." Use gerunds as subjects, after prepositions, after certain verbs, and after certain expressions.


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