Mastering Infinitives in English Grammar: A Comprehensive Guide
Understanding infinitives is essential for mastering English grammar. Infinitives serve as foundational elements in constructing sentences that express purpose, intent, or intention.
They are versatile and appear in various grammatical functions, making them vital for both beginner and advanced learners. Whether you’re learning English as a second language or aiming to refine your writing skills, a thorough grasp of infinitives will enhance your ability to communicate clearly and accurately.
This comprehensive guide explores every aspect of infinitives — from their basic structure to their complex usages and exceptions — providing learners with detailed explanations, numerous examples, practice exercises, and tips for mastery.
Table of Contents
- Definition of Infinitives
- Structural Breakdown of Infinitives
- Types and Categories of Infinitives
- Extensive Examples of Infinitives
- Usage Rules for Infinitives
- Common Mistakes and How to Avoid Them
- Practice Exercises
- Advanced Topics in Infinitive Usage
- Frequently Asked Questions
- Conclusion
1. Definition of Infinitives
In English grammar, an infinitive is the base form of a verb, usually preceded by the word to. It is considered a non-finite verb form because it does not show tense, person, or number on its own. Infinitives are incredibly versatile in English—they can function as nouns, adjectives, or adverbs within sentences, and they are often used to express purpose, intent, or future action.
For example, in the sentence “She wants to learn Spanish,” the phrase to learn is an infinitive functioning as the object of the verb wants. Similarly, in “To travel the world is my dream,” the infinitive phrase to travel the world functions as the subject of the sentence.
Classification and Function
Infinitives are classified as non-finite verb forms, meaning they do not carry tense or agree with the subject in number or person. They are often called the “to-infinitive” because of the particle to that typically accompanies the base verb. However, infinitives can sometimes appear without to, especially after modal verbs or in certain idiomatic expressions.
Contexts in Which Infinitives Are Used
- As a noun: To know her is to love her.
- As an adjective: She has a paper to write.
- As an adverb: He paused to think.
- In purpose or intent: I went to the store to buy bread.
- After certain verbs: She hopes to visit France.
- After adjectives: It’s difficult to understand.
2. Structural Breakdown of Infinitives
The basic structure of an infinitive is straightforward but involves specific patterns that learners should recognize:
| Component | Description | Example |
|---|---|---|
| Particle | The word to that precedes the base verb (except in certain cases) | to eat, to run, to read |
| Base verb | The root form of the verb without tense or inflection | eat, run, read |
Note that sometimes the particle to can be omitted, especially after modal verbs or certain expressions. These are called bare infinitives.
Pattern Summary:
- Full infinitive: to + base verb (e.g., to go, to see)
- Bare infinitive: base verb without to (e.g., after modal verbs)
3. Types and Categories of Infinitives
Infinitives can be categorized based on their function and usage within sentences. Understanding these categories helps learners recognize how infinitives operate and how they differ from other verb forms.
3.1. The Full Infinitive (to + verb)
This is the most common form and is used in a variety of grammatical constructions.
3.2. The Bare Infinitive (without to)
Often used after modal verbs, certain verbs of perception, and causative verbs.
3.3. Infinitive as a Noun
Acts as the subject or object of a sentence.
3.4. Infinitive as an Adjective
Modifies a noun, often explaining purpose or intent.
3.5. Infinitive as an Adverb
Modifies a verb, adjective, or other adverbs, expressing purpose, reason, or result.
3.6. Split Infinitives
Occur when an adverb or other word separates to from the verb (e.g., to boldly go). Though once considered incorrect, split infinitives are now accepted in many contexts, especially for clarity or emphasis.
4. Extensive Examples of Infinitives
Below are comprehensive examples categorized by the function and type of infinitive. These will help illustrate the various uses and structures of infinitives in real sentences.
4.1. Infinitives as Subjects
| Example | Explanation |
|---|---|
| To travel the world is my dream. | Infinitive phrase acting as the subject of the sentence. |
| To read books enriches the mind. | Infinitive as the subject, with a singular verb. |
| To learn new languages is challenging. | Infinitive as subject; note the singular verb. |
| To cook healthy meals requires effort. | Infinitive subject; used to express requirement. |
| To succeed in life depends on perseverance. | Infinitive as subject expressing dependence. |
4.2. Infinitives as Objects
| Example | Explanation |
|---|---|
| I want to learn French. | Infinitive as the object of the verb want. |
| She decided to leave early. | Infinitive as the object of decided. |
| They hope to visit Japan. | Infinitive as the object of hope. |
| He promised to help us. | Infinitive as the object of promised. |
| We plan to go hiking tomorrow. | Infinitive as the object of plan. |
4.3. Infinitives as Modifiers (Adjectives)
| Example | Explanation |
|---|---|
| This is the chance to succeed. | Infinitive modifies chance, indicating purpose. |
| She has a lot of work to do. | Infinitive describes the work, specifying what needs to be done. |
| He found the solution to fix the problem. | Infinitive modifies solution. |
| We need a place to stay overnight. | Infinitive describes the purpose of place. |
| I have a book to read before class. | Infinitive describes the book, indicating its purpose. |
4.4. Infinitives as Adverbs
| Example | Explanation |
|---|---|
| He studies hard to improve his grades. | Infinitive explains purpose, modifying the verb studies. |
| She paused to think. | Infinitive explains why she paused. |
| I called him to ask for advice. | Infinitive indicates the purpose of the call. |
| They left early to catch the train. | Infinitive describes the purpose of leaving early. |
| He went to the store to buy milk. | Infinitive explains the purpose of his going. |
5. Usage Rules for Infinitives
Mastering the correct usage of infinitives involves understanding specific grammatical rules, common patterns, and exceptions. These rules guide when to use the full infinitive, bare infinitive, or other variations.
5.1. The “To” Infinitive
- Form: to + base verb
- Usage: Used as a noun, adjective, or adverb. Common after certain verbs, adjectives, and nouns.
- Examples: to run, to sing, to believe, to understand
5.2. The Bare Infinitive
- Form: Base verb without to
- Usage: After modal verbs (can, could, may, might, must, shall, should, will, would), causative verbs (make, let, have), and perception verbs (see, hear, feel, listen).
- Examples: She can swim. I made him apologize. They saw her leave.
5.3. Infinitives with “Too” and “Enough”
| Usage | Examples |
|---|---|
| Too + adjective + to + verb | It’s too cold to go outside. |
| Enough + to + verb | She is old enough to drive. |
5.4. Infinitive of Purpose
Infinitives often express purpose, as in “I study hard to succeed.”. The purpose infinitive usually follows adjectives, nouns, or verbs indicating intention.
5.5. Infinitives after Certain Verbs
- Verbs of desire: want, wish, hope, desire
- Verbs of decision: decide, choose, determine
- Verbs of preference: would like, would love
- Verbs of expectation or planning: plan, intend, expect
5.6. Infinitives Without “to” (Bare Infinitives)
They appear after modal verbs and certain expressions, such as:
- Can, could, may, might, must, shall, should, will, would
- Causative verbs: make, let, have
- Perception verbs: see, hear, feel, watch
6. Common Mistakes and How to Avoid Them
Even experienced learners often make mistakes with infinitives. Recognizing these errors can significantly improve accuracy.
6.1. Using “to” with Modal Verbs
Incorrect: She can to swim.
Correct: She can swim.
6.2. Omitting “to” After Certain Verbs
Incorrect: I want learn.
Correct: I want to learn.
6.3. Using the Wrong Form after Verbs
Incorrect: She hopes to going.
Correct: She hopes to go.
6.4. Confusing Infinitives and Gerunds
Some verbs are followed by either a gerund or an infinitive, with different meanings.
| Verb | Meaning with Gerund | Meaning with Infinitive |
|---|---|---|
| Stop | Cease doing something | Decide to do something |
| Remember | Recall past action | Remember to do something in the future |
| Try | Experiment with something | Make an effort to do something |
7. Practice Exercises
Exercise Set 1: Fill in the blanks with the correct form of the infinitive (with or without “to”)
| Question | Options | Answer |
|---|---|---|
| I want ___ (buy) a new car. | to buy / buy | to buy |
| She can ___ (swim) very fast. | to swim / swim | swim |
| They decided ___ (leave) early. | to leave / leave | to leave |
| He hopes ___ (get) a promotion. | to get / get | to get |
| We plan ___ (visit) Paris next summer. | to visit / visit | to visit |
Exercise Set 2: Correct the errors in the following sentences
| Sentence | Correction |
|---|---|
| She wants to to go shopping. | She wants to go shopping. |
| I can to help you. | I can help you. |
| He decided to to stay home. | He decided to stay home. |
| They hope to to arrive early. | They hope to arrive early. |
| She promised to help us. | Correct as is. |
8. Advanced Topics in Infinitive Usage
For advanced learners, infinitives involve more nuanced uses, such as their role in complex sentences, passive constructions, and stylistic variations.
8.1. Infinitives in Passive Constructions
Passive infinitives occur in sentences where the subject receives the action expressed by the infinitive.
- Example: She is eager to be promoted.
- Form: to be + past participle (e.g., to be done, to be seen)
8.2. Infinitives in Reported Speech
When reporting speech, infinitives often appear after verbs like say or tell.
- Example: He said that he wanted to leave.
8.3. Infinitives in Conditional Sentences
Infinitives can express purpose in conditional sentences, especially in formal or literary styles.
- Example: To succeed, you must work hard.
8.4. Split Infinitives and Stylistic Choices
While traditionally discouraged, split infinitives are now often accepted for emphasis or clarity. For example, to boldly go where no man has gone before.
8.5. Infinitives in Formal and Literary English
In formal writing, infinitives are often used to convey purpose or intent with elegance and clarity.
9. Frequently Asked Questions (FAQ)
Q1: Can infinitives be used as subjects in sentences?
Yes. Infinitives can function as subjects, as in To learn is important.
Q2: When do I omit the “to” in infinitives?
After modal verbs and certain causative or perception verbs, the infinitive appears without to.
Q3: Are there verbs that are followed by both gerunds and infinitives with different meanings?
Yes. Examples include stop, remember, and try. The meaning changes depending on whether a gerund or infinitive follows.
Q4: Is it correct to split an infinitive with an adverb?
Yes. Example: to boldly go. Modern style often accepts split infinitives for clarity or emphasis.
Q5: What is a “bare infinitive,” and when is it used?
The bare infinitive is the base form of the verb without to. It is used after modal verbs, causative verbs, and perception verbs.
Q6: How do I distinguish between infinitives and other verb forms?
Infinitives are characterized by the particle to + base verb, but they can also occur without to in certain cases. Recognizing their function in the sentence helps in identification.
Q7: Can infinitives be used in complex sentences involving multiple clauses?
Yes. Infinitives can be embedded within complex sentences, often expressing purpose, intent, or result.
Q8: Are there idiomatic expressions involving infinitives?
Absolutely. Examples include to be or not to be, to cut a long story short, and to make matters worse.
10. Conclusion
Infinitives are a fundamental and versatile component of English grammar. They serve multiple roles, from expressing purpose to acting as subjects, objects, and modifiers in sentences.
Understanding the structural rules, different types, and proper usage of infinitives allows learners to communicate more effectively and confidently. Practice with diverse examples and exercises will deepen your mastery of this crucial grammatical form.
Remember that exceptions and stylistic choices, such as split infinitives, are part of natural language use. With consistent practice and awareness, mastering infinitives will significantly enhance your English language proficiency.