Infinitives are a fundamental and versatile part of English grammar, often appearing in various forms and serving multiple functions within a sentence. Understanding their structure and usage is key to mastering complex sentence construction and expressing nuanced meanings. This guide aims to demystify infinitives, providing clear explanations and practical examples to enhance your command of the English language.
We will delve into the core concepts, exploring how infinitives are formed, the different types that exist, and the roles they play in sentence structure. By breaking down these elements, you’ll gain a solid foundation for identifying and utilizing infinitives effectively in your own writing and speech.
Understanding the Infinitive Form
The infinitive is the base form of a verb, typically preceded by the word “to.” This “to” is known as the infinitive marker. For example, in the phrase “to run,” “run” is the base verb, and “to” marks it as an infinitive. This structure is the most common and recognizable form of the infinitive.
However, it’s important to note the existence of the “bare infinitive,” which is the base form of the verb without the “to.” This form appears in specific grammatical contexts, often after certain verbs or auxiliary verbs. Recognizing both forms is crucial for accurate grammatical analysis.
The infinitive can function as a noun, an adjective, or an adverb, making it a highly flexible grammatical element. Its ability to adapt to these different roles allows for a wide range of expression and sentence complexity. Mastering these functions unlocks a deeper understanding of sentence structure.
The Infinitive as a Noun
When an infinitive acts as a noun, it can be the subject of a sentence, the direct object, or a subject complement. As a subject, it performs the action of the main verb. For instance, “To err is human” uses the infinitive “to err” as the subject of the verb “is.”
The infinitive can also receive the action of a verb, functioning as a direct object. In the sentence “She wants to travel,” the infinitive “to travel” is what she wants. This is a common construction where the infinitive clarifies the object of desire or intention.
Furthermore, an infinitive can serve as a subject complement, renaming or describing the subject after a linking verb. Consider the sentence “Her goal is to win.” Here, “to win” renames “goal,” explaining what her goal is. This use often follows forms of the verb “to be.”
Infinitives as Subjects
Using infinitives as subjects can make sentences more formal or emphatic. For example, “To understand is to forgive” places the infinitive phrase at the beginning for emphasis. This structure highlights the action itself as the primary focus.
It’s common to see these subject infinitives followed by a comma if they are lengthy, though not strictly required. “To build a successful business requires dedication and hard work” is a clear example of an infinitive phrase functioning as the subject. The entire phrase “To build a successful business” acts as a single unit.
When an infinitive functions as the subject, it’s important to remember that it represents a concept or an action. This abstract nature allows it to stand in for a concrete noun in many situations. The verb in the main clause will agree with the singular nature of the infinitive subject.
Infinitives as Direct Objects
Many verbs in English are followed by infinitive phrases as their direct objects. These verbs often express desire, intention, or opinion. Examples include “like,” “love,” “want,” “need,” “hope,” “expect,” “decide,” “plan,” and “agree.”
In the sentence “They decided to leave early,” the infinitive phrase “to leave early” is the direct object of the verb “decided.” It answers the question “What did they decide?” This structure is straightforward and frequently encountered in everyday English.
Some verbs can also be followed by a noun or pronoun before the infinitive, creating an object complement structure. For instance, “He asked me to help him.” Here, “me” is the object of “asked,” and “to help him” is the infinitive phrase explaining what he asked. This expands the complexity of infinitive usage.
Infinitives as Subject Complements
Following linking verbs like “is,” “am,” “are,” “was,” “were,” “seems,” “appears,” and “becomes,” infinitives can function as subject complements. They provide more information about the subject. “My ambition is to become a doctor” clearly illustrates this.
In this case, “to become a doctor” describes or renames the subject “ambition.” It clarifies the nature of the ambition. The infinitive phrase completes the meaning of the linking verb by referring back to the subject.
This usage helps to define or explain the subject’s state or identity. “The best way to learn is by doing” shows how an infinitive complement can offer advice or a general truth. The infinitive phrase provides the essential information about “the best way.”
The Infinitive as an Adjective
When an infinitive phrase modifies a noun or pronoun, it acts as an adjective. It answers questions like “Which one?” or “What kind?” For example, in “I need a book to read,” the infinitive phrase “to read” modifies the noun “book.”
This adjectival function often follows the noun it describes, much like a relative clause. “She has a lot of work to do” uses “to do” to specify what kind of work she has. The infinitive phrase provides essential detail about the noun.
The placement of the infinitive phrase is typically immediately after the noun or pronoun it modifies. This proximity ensures clarity and avoids ambiguity. “He is looking for a place to stay” clearly indicates the purpose of the place he seeks.
Infinitives Modifying Nouns
Consider the sentence “We need a plan to succeed.” The infinitive “to succeed” describes the noun “plan,” telling us the purpose of the plan. It functions as a post-modifying adjective.
Another example is “She bought some cookies to share.” The phrase “to share” modifies “cookies,” indicating their intended use. This adjectival role is common for expressing purpose or intended action related to a noun.
These adjectival infinitives can sometimes be rephrased using relative clauses, such as “We need a plan that will help us succeed.” However, the infinitive form is often more concise and natural sounding.
Infinitives Modifying Pronouns
Infinitives can also modify pronouns, though this is less common than modifying nouns. For instance, “Is there anything to eat?” uses “to eat” to modify the pronoun “anything.” It specifies the purpose or nature of “anything.”
In sentences with indefinite pronouns like “something,” “anything,” “nothing,” or “someone,” an infinitive phrase often follows. “He has something important to tell you” uses “to tell you” to describe “something.” The infinitive clarifies what the “something” is about.
These constructions are idiomatic and contribute to the fluid expression of ideas. They allow for precise description without lengthy clauses. Understanding this function is key to interpreting subtle nuances in meaning.
The Infinitive as an Adverb
Infinitives frequently function as adverbs, explaining the reason for or purpose of an action. They often answer the questions “Why?” or “To what end?” In “He studied hard to pass the exam,” the infinitive phrase “to pass the exam” explains why he studied hard.
Adverbial infinitives can appear at the beginning or end of a sentence, and sometimes in the middle. They provide context and motivation for the main clause’s action. “To succeed, you must work diligently” uses the infinitive to state a condition for success.
This adverbial role is crucial for conveying purpose and intent. It adds a layer of explanation to the primary statement of the sentence. Recognizing this function helps in understanding the underlying reasons behind actions described in a text.
Infinitives Expressing Purpose
The most common adverbial function of infinitives is to express purpose. These phrases often answer the question “Why did someone do that?” For example, “She went to the store to buy milk.”
The infinitive phrase “to buy milk” clearly states the reason for her going to the store. This is a very common and direct way to express the goal of an action. It’s a highly efficient grammatical structure.
Sentences can easily incorporate this structure to explain motivations. “He saved money to buy a car” uses the infinitive to explain the purpose of his saving. This is a fundamental aspect of expressing intent.
Infinitives Expressing Result or Consequence
In some cases, infinitives can express a result or consequence, especially after certain adjectives or verbs. For instance, “He was surprised to see her there.” The infinitive “to see her there” explains the cause of his surprise.
This usage often follows adjectives that describe emotions or states of being. “I am happy to help you” uses “to help you” to indicate the reason for happiness. It connects an emotion to a specific action or circumstance.
The infinitive here highlights the reaction to a situation. “They were sorry to hear the news” shows how an infinitive can explain the cause of regret or sadness. It provides the specific trigger for the feeling.
The Bare Infinitive
The bare infinitive is the base form of the verb without “to.” It appears after certain modal verbs and specific constructions. Modal verbs like “can,” “could,” “will,” “would,” “shall,” “should,” “may,” “might,” and “must” are always followed by bare infinitives.
For example, “You must go now.” The verb “go” is in its bare infinitive form. This rule applies consistently across all modal verbs and their past tense counterparts. “She can swim” also uses a bare infinitive.
Other instances include verbs of perception like “see,” “hear,” “feel,” and “watch” when followed by an object. “I saw him leave” uses the bare infinitive “leave.” This distinguishes it from constructions that might use a gerund or a full infinitive.
Bare Infinitives After Modal Verbs
Modal verbs express possibility, necessity, ability, or permission, and they are intrinsically linked to bare infinitives. “He will arrive soon.” The verb “arrive” is a bare infinitive.
This grammatical rule is consistent and essential for correct modal verb usage. “They might forget” uses “forget” as a bare infinitive following “might.” There is no exception to this pattern.
Understanding this distinction is vital, as using “to” with a modal verb results in an ungrammatical sentence. “She should to study” is incorrect; it should be “She should study.” This is a fundamental aspect of English verb conjugation.
Bare Infinitives After Verbs of Perception
Verbs like “see,” “hear,” “feel,” “notice,” and “watch” can be followed by a direct object and a bare infinitive to describe a complete action observed. “We heard the music play.” The bare infinitive “play” indicates the entire action of the music being heard.
If a gerund (verb ending in -ing) is used instead of a bare infinitive, it suggests observing an action in progress. “We heard the music playing” implies hearing the music for a duration. The choice between bare infinitive and gerund subtly alters the meaning.
This construction is common for reporting sensory experiences. “I saw her walk away” uses the bare infinitive “walk” to denote the completed action of walking away. It’s a concise way to describe what was perceived.
Bare Infinitives After “Let,” “Make,” and “Help”
The verbs “let” (to allow), “make” (to force), and “help” are followed by an object and a bare infinitive. “Let me go.” The verb “go” is a bare infinitive after the object “me.”
Similarly, “The teacher made the students stay late.” “Stay” is the bare infinitive following “students.” This pattern is consistent for these three specific verbs. “He helped her move the furniture” uses “move” as a bare infinitive.
Note that “help” can also be followed by a full infinitive (“help her to move”), but the bare infinitive is more common and often preferred for conciseness. Both are grammatically correct, but the bare infinitive is frequently used in everyday speech.
Infinitive Phrases
An infinitive phrase includes the infinitive itself, plus any modifiers or objects associated with it. These phrases function as a single unit within a sentence, acting as a noun, adjective, or adverb. “To finish the project on time” is an infinitive phrase.
This phrase contains the infinitive “to finish” and its object “the project” along with the adverbial phrase “on time.” Understanding the components of an infinitive phrase is key to parsing complex sentences.
The entire phrase functions grammatically, allowing for more elaborate sentence construction. For example, “To finish the project on time was her main priority.” Here, the entire phrase acts as the subject.
Structure of Infinitive Phrases
The core of an infinitive phrase is the infinitive verb (e.g., “to walk”). It can be modified by adverbs (“to walk quickly”) or followed by objects (“to walk the dog”). Prepositional phrases can also be part of the structure (“to walk in the park”).
The phrase functions as a single grammatical element. “She wants to learn a new language fluently.” The phrase “to learn a new language fluently” acts as the direct object of “wants.”
Recognizing the boundaries of the phrase is important for clarity. The infinitive marker “to” always precedes the base verb, and everything that follows and modifies or completes the verb’s meaning is part of the phrase. This creates a cohesive unit of meaning.
Using Adverbs Within Infinitive Phrases
Adverbs can modify the infinitive verb within an infinitive phrase. They often describe how, when, where, or to what extent the action of the infinitive occurs. “He tried to diligently complete his work.”
The adverb “diligently” modifies the infinitive “to complete,” explaining how he tried to complete his work. Placement of the adverb can sometimes vary, but typically it comes directly before or after the infinitive.
Careful placement of adverbs ensures the intended meaning is conveyed clearly. “She wants to quickly finish her meal” is correct, while “She wants quickly to finish her meal” sounds awkward and is less common.
Using Objects and Complements in Infinitive Phrases
Infinitives can take direct objects or be followed by complements, just as regular verbs do. “To bake a cake” includes the direct object “a cake.”
The infinitive phrase then becomes more complex and specific. “He plans to bake a delicious chocolate cake for the party.” This phrase includes the infinitive, its object, and further descriptive elements.
These extended phrases allow for detailed expression of actions and intentions. They form robust grammatical units that can serve various roles in a sentence. Understanding these components is key to grasping complex sentence structures.
Split Infinitives
A split infinitive occurs when an adverb or adverbial phrase is placed between “to” and the base verb of the infinitive. For example, “to boldly go.” This construction has been a subject of debate among grammarians.
While traditionally discouraged by some style guides, split infinitives are now widely accepted in modern English, especially when they improve clarity or flow. “He decided to really think about the offer.”
The key is to use them judiciously. Overuse or awkward placement can still sound unnatural or detract from the sentence’s elegance. Often, rephrasing can avoid a split infinitive if desired.
When to Use Split Infinitives
Split infinitives are often used for emphasis or to avoid ambiguity. “She promised to carefully consider all options.” Placing “carefully” before “to” (“She promised carefully to consider”) might lessen the emphasis on the carefulness.
In some cases, splitting the infinitive is the clearest way to convey the intended meaning. “He wants to seriously reconsider his decision.” Without the split, “He wants seriously to reconsider” sounds slightly less direct.
Consider the rhythm and emphasis you wish to achieve. If splitting an infinitive sounds natural and enhances the meaning, it is generally acceptable in contemporary usage. The famous Star Trek line “to boldly go” exemplifies a powerful and accepted split infinitive.
Avoiding Awkward Splits
While split infinitives are permissible, avoid placing long adverbial phrases between “to” and the verb, as this can create cumbersome sentences. “To in a very thoughtful and deliberate manner consider the proposal” is an example of an awkward split.
In such cases, moving the adverbial phrase can often improve the sentence structure. “To consider the proposal in a very thoughtful and deliberate manner” is a much smoother construction.
The goal is always clarity and readability. If a split infinitive sounds clunky or confusing, it’s best to rephrase the sentence. Simplicity and directness often lead to better communication.
Infinitives vs. Gerunds
Infinitives and gerunds are both verb forms that can function as nouns, which often leads to confusion. A gerund is the -ing form of a verb used as a noun (e.g., “swimming is fun”).
The choice between using an infinitive or a gerund often depends on the preceding verb or preposition. Some verbs are followed by infinitives, while others are followed by gerunds. “I like to swim” (infinitive) vs. “I enjoy swimming” (gerund).
Understanding which form to use after specific verbs is a key aspect of mastering English grammar. Context and the specific verb dictate the correct choice. This distinction is crucial for grammatical accuracy.
Verbs Followed by Infinitives
Many verbs are typically followed by infinitives. These often express desire, intention, decision, or expectation. Common examples include “want,” “hope,” “plan,” “decide,” “agree,” “promise,” “expect,” and “need.”
For example, “She hopes to visit Paris next year.” The infinitive “to visit” follows the verb “hopes.” This pattern is consistent for this group of verbs.
Learning these verb patterns is essential for correct usage. Memorizing common verbs that take infinitives will significantly improve your fluency and accuracy. “He decided to study abroad” is another standard example.
Verbs Followed by Gerunds
Conversely, certain verbs are followed by gerunds. These often express enjoyment, aversion, continuation, or completion of an action. Examples include “enjoy,” “avoid,” “finish,” “mind,” “suggest,” “consider,” and “practice.”
For instance, “They enjoy playing chess.” The gerund “playing” follows the verb “enjoy.” This is a standard construction for this category of verbs.
Mastering this list is as important as knowing the verbs that take infinitives. “He finished reading the book” correctly uses the gerund “reading.” The distinction is vital for grammatical correctness.
Verbs Followed by Either (with Meaning Change)
Some verbs can be followed by either an infinitive or a gerund, but the meaning of the sentence changes. “Remember” is a prime example: “I remember to lock the door” (I recalled that I had to lock it and did so) versus “I remember locking the door” (I have a memory of the act of locking it).
Another such verb is “stop.” “She stopped to smoke” (she ceased her current activity in order to smoke) versus “She stopped smoking” (she quit the habit of smoking). The infinitive indicates purpose, while the gerund indicates cessation.
These nuanced differences highlight the importance of context and the specific verb choice. Paying attention to these distinctions allows for more precise and sophisticated expression. “Try to solve the problem” (make an effort) versus “Try solving the problem” (experiment with a method).
The Infinitive of Purpose
As briefly touched upon, the infinitive of purpose is a common adverbial use, explaining why an action is performed. It answers the question “Why?” and is often interchangeable with phrases like “in order to” or “so as to.”
Consider the sentence “He is saving money to buy a house.” The infinitive “to buy a house” explains the purpose of saving money. This is a direct and concise way to express intent.
This structure is fundamental for explaining motivations and goals. It’s a widely used and easily understood grammatical construction. “She called me to ask for help.”
Forming the Infinitive of Purpose
The infinitive of purpose is formed simply by using the “to” + base verb structure. It directly follows the main clause or action it explains. “We went to the library to borrow some books.”
The phrase “to borrow some books” clearly states the reason for going to the library. This directness makes it a preferred choice in many contexts for its conciseness.
It can also be placed at the beginning of a sentence for emphasis, though this is less common. “To succeed in this field, one must be dedicated.” The structure remains consistent, emphasizing the goal.
Using “In Order To” and “So As To”
“In order to” and “so as to” are more formal ways to express purpose, often used to add emphasis or clarity, particularly in more formal writing. “He studied diligently in order to pass the examination.”
These phrases are essentially expanded versions of the infinitive of purpose. They serve the same grammatical function but add a slightly more formal tone. “She spoke slowly so as to be understood by everyone.”
While the simple infinitive of purpose is often sufficient, these longer phrases can be useful for specific stylistic effects or when absolute clarity is paramount. They reinforce the idea of deliberate intention.
Common Mistakes with Infinitives
One common mistake is the incorrect use of gerunds instead of infinitives after certain verbs. For example, saying “I want going” instead of “I want to go.” This often stems from confusion between verbs that take infinitives and those that take gerunds.
Another error involves the misuse of the bare infinitive, for instance, “She should to go.” As discussed, modal verbs are followed by bare infinitives, not full ones. This is a frequent point of error for learners.
Misplacing adverbs within infinitive phrases can also lead to awkwardness or ambiguity. “He wanted to quickly eat” is generally preferred over “He wanted quickly to eat.” Careful placement ensures clarity.
Incorrect Verb Choices (Infinitive vs. Gerund)
The most prevalent error is choosing the wrong form after a verb. Forgetting that verbs like “enjoy” take gerunds (“I enjoy to read”) is common. The correct form is “I enjoy reading.”
Conversely, using a gerund after a verb that requires an infinitive is also frequent. “They suggested going to the park” is correct, but “They decided going to the park” is incorrect; it should be “They decided to go to the park.”
Consistent practice and memorization of verb patterns are the best remedies for this type of error. Focusing on common verbs will build a strong foundation.
Errors with Bare Infinitives
Using “to” with modal verbs like “can,” “will,” or “must” is a persistent error. “You must to be quiet” is grammatically incorrect. The correct sentence is “You must be quiet.”
Similarly, verbs of perception like “see” or “hear” are followed by bare infinitives, not full ones, when describing a complete action. “I saw him to cross the street” is wrong; it should be “I saw him cross the street.”
These errors often arise from overgeneralization or applying rules incorrectly. Remembering the specific contexts for bare infinitives is crucial.
Problems with Infinitive Phrases
Ambiguity can arise from poorly constructed infinitive phrases, especially when they are long or their placement is unclear. “She told him to go to the store to buy milk for the baby that was crying.” The relative clause “that was crying” could ambiguously refer to the baby or the milk.
Another issue is the dangling infinitive, where the phrase seems to modify something other than its intended subject. “To improve his grades, the homework was completed diligently.” The homework did not intend to improve its own grades.
Ensuring that the infinitive phrase clearly relates to the subject performing the action is key. Rephrasing often resolves these structural problems. “He completed the homework diligently to improve his grades.”