Learn on PengiElements of Language, 2nd CourseChapter 5: The Phrase: Prepositional, Verbal, and Appositive Phrases

Lesson 4: The Infinitive and the Infinitive Phrase

In this Grade 5 grammar lesson from Elements of Language, 2nd Course, students learn to identify and use infinitives and infinitive phrases, understanding how a verb form beginning with "to" can function as a noun, adjective, or adverb in a sentence. The lesson also teaches students to distinguish infinitives from prepositional phrases and to recognize the complete infinitive phrase, including any modifiers or complements. Practice exercises guide students through identifying infinitives and infinitive phrases in context.

Section 1

The Infinitive

Definition

An infinitive is a verb form that can be used as a noun, an adjective, or an adverb. Most infinitives begin with to.

Explanation

An infinitive is the basic form of a verb, like 'to run' or 'to jump'. Think of it as the verb's "to do" form! It can act like a noun, adjective, or adverb. A handy trick to spot one is to look for the word to followed immediately by a verb. If to is followed by a noun, it's likely part of a prepositional phrase, not an infinitive.

Examples

  • We went to the park to play! [The first 'to' is a preposition because it's followed by the noun park. The second 'to' is part of the infinitive to play because it's followed by the verb 'play'.]
  • Do you need to leave? [Is the word to followed by a verb? Yes! So, 'to leave' is the infinitive.]
  • The movie was too scary to be watched. [The word 'to' is followed by the verb 'be watched', so to be watched is the infinitive.]

Section 2

The Infinitive Phrase

Definition

An infinitive phrase consists of an infinitive and any modifiers or complements the infinitive has. The entire phrase can be used as a noun, an adjective, or an adverb.

Explanation

An infinitive phrase is a team of words starting with an infinitive (like 'to eat'). The rest of the team includes words that describe or complete the infinitive's action. The entire phrase works together as a single part of speech—either a noun, an adjective, or an adverb. It’s the infinitive plus all its extra details.

Examples

  • No, the soup is too hot to eat right now. [The infinitive is 'to eat'. The words 'right now' modify the infinitive, so the whole infinitive phrase is 'to eat right now'.]
  • Do you want to visit another country? [The infinitive is 'to visit'. The words 'another country' complete the action. The infinitive phrase is 'to visit another country'.]
  • To learn a new skill, you must practice every day. [Is 'to' followed by a verb? Yes, 'learn'. The words 'a new skill' complete the action, so the infinitive phrase is 'to learn a new skill'.]

Book overview

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Chapter 5: The Phrase: Prepositional, Verbal, and Appositive Phrases

  1. Lesson 1

    Lesson 1: The Phrase

  2. Lesson 2

    Lesson 2: The Prepositional Phrase

  3. Lesson 3

    Lesson 3: The Participle and the Participial Phrase

  4. Lesson 4Current

    Lesson 4: The Infinitive and the Infinitive Phrase

  5. Lesson 5

    Lesson 5: Appositives and Appositive Phrases

Lesson overview

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Section 1

The Infinitive

Definition

An infinitive is a verb form that can be used as a noun, an adjective, or an adverb. Most infinitives begin with to.

Explanation

An infinitive is the basic form of a verb, like 'to run' or 'to jump'. Think of it as the verb's "to do" form! It can act like a noun, adjective, or adverb. A handy trick to spot one is to look for the word to followed immediately by a verb. If to is followed by a noun, it's likely part of a prepositional phrase, not an infinitive.

Examples

  • We went to the park to play! [The first 'to' is a preposition because it's followed by the noun park. The second 'to' is part of the infinitive to play because it's followed by the verb 'play'.]
  • Do you need to leave? [Is the word to followed by a verb? Yes! So, 'to leave' is the infinitive.]
  • The movie was too scary to be watched. [The word 'to' is followed by the verb 'be watched', so to be watched is the infinitive.]

Section 2

The Infinitive Phrase

Definition

An infinitive phrase consists of an infinitive and any modifiers or complements the infinitive has. The entire phrase can be used as a noun, an adjective, or an adverb.

Explanation

An infinitive phrase is a team of words starting with an infinitive (like 'to eat'). The rest of the team includes words that describe or complete the infinitive's action. The entire phrase works together as a single part of speech—either a noun, an adjective, or an adverb. It’s the infinitive plus all its extra details.

Examples

  • No, the soup is too hot to eat right now. [The infinitive is 'to eat'. The words 'right now' modify the infinitive, so the whole infinitive phrase is 'to eat right now'.]
  • Do you want to visit another country? [The infinitive is 'to visit'. The words 'another country' complete the action. The infinitive phrase is 'to visit another country'.]
  • To learn a new skill, you must practice every day. [Is 'to' followed by a verb? Yes, 'learn'. The words 'a new skill' complete the action, so the infinitive phrase is 'to learn a new skill'.]

Book overview

Jump across lessons in the current chapter without opening the full course modal.

Continue this chapter

Chapter 5: The Phrase: Prepositional, Verbal, and Appositive Phrases

  1. Lesson 1

    Lesson 1: The Phrase

  2. Lesson 2

    Lesson 2: The Prepositional Phrase

  3. Lesson 3

    Lesson 3: The Participle and the Participial Phrase

  4. Lesson 4Current

    Lesson 4: The Infinitive and the Infinitive Phrase

  5. Lesson 5

    Lesson 5: Appositives and Appositive Phrases