Which Sentence Contains An Infinitive

Identifying Sentences Containing Infinitives: A Comprehensive Guide

Understanding infinitives is crucial for mastering grammar and sentence structure in English. This article will provide a detailed explanation of what infinitives are, how to identify them in sentences, and explore various examples to solidify your understanding. We'll delve into the function of infinitives, common mistakes, and even look at some more complex sentence structures. By the end, you'll be able to confidently pinpoint sentences containing infinitives and understand their role in constructing clear and impactful communication.

What is an Infinitive?

An infinitive is the base form of a verb, preceded by the word "to." It's essentially the most basic form of the verb, before it's conjugated for tense, person, or number. Think of it as the verb in its purest, unadorned form. For example, the infinitive of the verb "to run" is simply "to run." Other examples include "to eat," "to sleep," "to sing," "to be," and "to go."

It's important to distinguish the infinitive ("to + verb") from a prepositional phrase beginning with "to." A prepositional phrase will have a noun or pronoun as its object, while an infinitive phrase will contain a verb (though it might also include other elements like adverbs or objects).

Identifying Infinitives in Sentences: A Step-by-Step Guide

Identifying sentences containing infinitives involves a simple two-step process:

Look for "to" followed by a verb: This is the primary identifier. If you see "to" followed by a verb in its base form (not conjugated), you've likely found an infinitive.
Check the function of the "to" + verb phrase: Does it act as a noun, adjective, or adverb within the sentence? The infinitive can function differently in a sentence which we will explore in more detail further down.

Examples of Sentences Containing Infinitives

Let's examine several sentences, highlighting the infinitives and explaining their function:

Example 1: I want to travel the world.
- Here, "to travel" is the infinitive and functions as the object of the verb "want." We want what? To travel.
Example 2: She needs to study harder for the exam.
- In this sentence, "to study" is the infinitive and acts as the object of the verb "needs." She needs what? To study.
Example 3: His goal is to become a doctor.
- Here, "to become" functions as a noun phrase that is the subject complement of the verb "is." His goal is what? To become a doctor.
Example 4: They decided to leave early.
- "To leave" is the infinitive, acting as the object of the verb "decided." They decided what? To leave.
Example 5: It is important to understand the instructions carefully.
- "To understand" acts as the subject complement after the linking verb "is." It is what? To understand.
Example 6: The best way to learn a language is through immersion.
- "To learn" functions as an adjective modifying the noun phrase "best way." Which way? The best way to learn.
Example 7: He ran to catch the bus.
- "To catch" functions as an adverb indicating purpose – why did he run? To catch the bus.
Example 8: I am happy to help you.
- "To help" acts as an adjective describing the subject ("I"). Happy in what way? Happy to help.

Infinitives as Nouns

Infinitives can function as nouns in a sentence, acting as subjects, objects, or complements.

Subject: To err is human. (Infinitive phrase "to err" acts as the subject of the sentence).
Object: I hope to see you soon. (Infinitive phrase "to see" is the object of the verb "hope").
Complement: My ambition is to succeed. (Infinitive phrase "to succeed" completes the meaning of the linking verb "is").

Infinitives as Adjectives

Infinitives can modify nouns, acting as adjectives.

Example: I have a lot of work to do. ("to do" modifies "work").
Example: He gave me instructions to follow. ("to follow" modifies "instructions").

Infinitives as Adverbs

Infinitives can also function as adverbs, often indicating purpose, result, or reason.

Example: She studied hard to pass the exam. ("to pass" explains the reason for studying hard).
Example: He ran fast to catch the train. ("to catch" explains the purpose of running).

Bare Infinitives

While most infinitives are preceded by "to," some verbs use bare infinitives (infinitives without "to"). These verbs include:

Modal verbs: can, could, may, might, must, shall, should, will, would. Example: I can go.
Perception verbs: feel, hear, see, watch, observe. Example: I saw him leave.
Helping verbs: do, does, did. Example: Did you see it? (Note that even here, the "see" is a base form; it is still an infinitive but not preceded by "to").
Let, make, help: These are a bit more complex, as they can use bare infinitives or infinitives with "to." The choice often depends on the nuance of the sentence and style of writing.

Common Mistakes in Identifying Infinitives

A frequent mistake is confusing infinitives with prepositional phrases starting with "to." Remember, a prepositional phrase will always have a noun or pronoun as its object. An infinitive will have a verb.

Infinitive: I want to go to the park. ("to go" is the infinitive; "park" is its object)
Prepositional Phrase: I went to the park. ("to" is a preposition; "park" is its object)

Another mistake arises when encountering bare infinitives. While not all infinitives use "to," the base form of the verb still indicates its infinitive nature.

Complex Sentence Structures with Infinitives

Infinitives can appear in complex sentence structures, sometimes nested within other clauses or phrases. These can be challenging to parse but applying the principles discussed earlier will help you identify them:

Example: She decided to try to learn a new language. ("to try" and "to learn" are both infinitives; "to learn" is the object of "to try").
Example: The plan was to make sure to complete the project on time. ("to make sure" and "to complete" are both infinitives; "to complete" is the object of "to make sure").

Frequently Asked Questions (FAQs)

Q: Can an infinitive be part of a phrase? A: Yes, infinitives are often the head of infinitive phrases. These phrases can include adverbs, objects, or other modifiers that expand upon the meaning of the infinitive.
Q: Can an infinitive be split? A: Yes, it's grammatically acceptable to place modifiers between "to" and the verb. However, it's generally advisable to avoid splitting infinitives to enhance readability and flow.
Q: What is the difference between an infinitive and a gerund? A: An infinitive is a verb preceded by "to" (usually). A gerund is a verb ending in "-ing" functioning as a noun. Example: To sing is enjoyable (infinitive). Singing is enjoyable (gerund).
Q: How can I improve my ability to identify infinitives? A: Practice! Read widely, paying attention to sentence structure. Try diagramming sentences to visualize their grammatical relationships. And continue reviewing examples.

Conclusion

Identifying infinitives in sentences is a fundamental skill for understanding and constructing grammatically correct English sentences. By recognizing the "to + verb" structure and considering the function of the infinitive within the sentence (noun, adjective, or adverb), you can master this important aspect of English grammar. Remember to look out for bare infinitives as well. With practice and consistent application of these guidelines, you’ll gain confidence in analyzing sentence structure and improving your writing skills significantly. The key is to practice and to carefully examine the function of the infinitive phrase within the overall sentence. Keep practicing, and you will soon become an expert at identifying these essential parts of speech!