Infinitive Clauses and Phrases

What’s an Infinitive?

An infinitive is the base form of a verb preceded by “to.” Also referred as “to infinitive”

• Verb: run
• Infinitive: to run
• Verb: eat
• Infinitive: to eat
• Verb: sleep
• Infinitive: to sleep

Infinitives can function as nouns, adjectives, or adverbs in a sentence. This versatility is what makes them so powerful!

Important Note: While the “base form” of a verb (like run, eat, sleep) is sometimes called a “bare infinitive,” when we talk about the “infinitive” in general English grammar, we almost always mean the “to-infinitive” (like to run, to eat, to sleep). This is the form we’ll be focusing on here!

⏰ When do we use infinitive clauses and phrases?

We use infinitives to:

Express purpose (why something is done):

• Many organizations take action to reduce carbon emissions.
• Efforts are being made to improve air quality in major cities.

Describe solutions and recommendations:

• One way to fight climate change is to use renewable energy.
• A key solution to reduce waste is to recycle more efficiently.

Explain responsibility and necessity:

• It is important to educate people about sustainable practices.
• Governments need to create stricter environmental laws.

Show consequences or results:

• Many organizations work with local communities to increase awareness.
• Factories must adopt cleaner energy policies to avoid heavy fines.

📌 Structure

An infinitive phrase is simply the infinitive "to" + verb plus any objects or modifiers that go with it. The whole phrase acts as a single unit in the sentence.

Examples of Infinitive Phrases:

• to study hard
• to buy a new car
• to help her friends
• to finish the project on time

Now, let’s see how these phrases function in sentences:

Infinitive Phrases: The “To + Verb” Unit (+ anything else!)

Infinitive Phrases as Nouns (Subject or Object)

Just like gerunds, infinitive phrases can act as the subject or object of a sentence.

As a Direct Object (after certain verbs): Many verbs are followed by an infinitive phrase as their direct object.

Common verbs: want, need, hope, decide, plan, learn, agree, seem, appear, promise, refuse, offer, manage, expect, choose.

I want to visit Japan next year. (What do I want? To visit Japan next year.)

She decided to study abroad. (What did she decide? To study abroad.)

They hope to finish the work by Friday. (What do they hope? To finish the work by Friday.)

Infinitive Phrases as Adjectives

An infinitive phrase can describe a noun or pronoun. It usually comes after the noun it modifies.

I have a lot of homework to do tonight. (What kind of homework? Homework to do.)

He’s looking for a good book to read. (What kind of book? A book to read.)

Is there anything to eat? (What kind of anything? Anything to eat.)

Infinitive Phrases as Adverbs (Expressing Purpose is Key!)

This is one of the most common and useful functions! Infinitive phrases often act as adverbs, usually to explain why something is done (purpose). You can often replace them with “in order to” or “so as to.”

She went to the library to study for her exam. (Why did she go? To study for her exam.)

He works hard to support his family. (Why does he work hard? To support his family.)

They saved money to buy a new house. (Why did they save money? To buy a new house.)

I called you to ask a question. (Why did I call you? To ask a question.):

Infinitive Clauses: When the Infinitive Has its Own Subject!

Sometimes, an infinitive phrase includes its own subject. When this happens, we call it an infinitive clause. The subject of the infinitive is usually an object pronoun (him, her, them, us, me, you, it) or a noun.

The structure is often: Verb + Object/Noun + Infinitive Phrase

Examples of Infinitive Clauses:

• I want her to call me. (The infinitive is “to call,” and “her” is the one doing the calling.)
• He asked me to help him. (The infinitive is “to help,” and “me” is the one doing the helping.)
• She told them to wait outside. (The infinitive is “to wait,” and “them” is the one doing the waiting.)
• They expect us to arrive on time. (The infinitive is “to arrive,” and “us” is the one doing the arriving.)
• It’s important for students to practice every day. (The infinitive is “to practice,” and “students” are the ones doing the practicing. Note the “for” before the subject when it’s not a direct object of the main verb.)

Key Difference: In an infinitive phrase, the subject of the infinitive is the same as the subject of the main verb (e.g., “I want to learn“). In an infinitive clause, the infinitive has a different subject (e.g., “I want her to learn“).bject or Object)