---
title: "Split Infinitives | English Grammar and Usage"
description: "Split infinitives are infinitives with an adverb between to and the verb, like \"to boldly go,\" and they show prescriptive versus descriptive usage."
canonical: "https://fiveable.me/english-grammar-usage/key-terms/split-infinitives"
type: "key-term"
subject: "English Grammar and Usage"
unit: "Unit 13"
---

# Split Infinitives | English Grammar and Usage

## Definition

A split infinitive is an infinitive with a word, usually an adverb, between to and the verb, like "to boldly go." In English Grammar and Usage, it’s a common usage issue tied to style and grammar debate.

## What It Is

A split infinitive is an infinitive phrase with a word placed between to and the base verb, usually an adverb. The classic example is "to boldly go," where boldly sits between to and go.

In English Grammar and Usage, this term shows up when you look at sentence structure and word order. An infinitive is the to-form of a verb, such as to write, to finish, or to clearly explain. When something splits that pair, you get a split infinitive. The structure is still recognizable as an infinitive, but the middle word can change the rhythm or emphasis of the sentence.

Writers have argued about split infinitives for a long time because of prescriptive grammar. Older style advice often told people to avoid them, partly because Latin infinitives are one word and cannot be split. But English is not Latin, and descriptive grammar looks at how English speakers actually use the language. From that viewpoint, a split infinitive is not automatically wrong. It is just one possible sentence pattern.

The real issue is often clarity and flow. Sometimes moving the adverb elsewhere makes the sentence stiffer or changes the meaning. Compare "She decided to carefully review the paper" with "She decided to review the paper carefully." Both are grammatical, but the first version keeps the adverb close to review and may sound more natural in some sentences.

That is why split infinitives are less about a hard rule and more about choice. In a grammar or usage class, you are usually asked to recognize the construction, explain why someone might avoid it, and decide whether it improves or weakens a sentence in context.

## Why It Matters

Split infinitives matter because they sit right at the intersection of grammar rules, style, and sentence effect. If you are studying prescriptive grammar, this is a perfect example of a rule that many people were taught as absolute but that modern usage treats more flexibly.

They also help you think about how English sentence rhythm works. Sometimes a split infinitive keeps an adverb next to the verb it modifies, which can make the meaning clearer. Other times, the split feels awkward because the adverb is too heavy, too long, or distracts from the main verb.

This term also shows up in editing and revision tasks. You may be asked to compare two versions of a sentence and explain which one is smoother, more precise, or better for a formal tone. That makes split infinitives a useful test of whether you can talk about grammar as a set of choices instead of a list of rigid bans.

## Connections

### Infinitive

You need to know what an infinitive is before you can spot a split infinitive. The split only happens inside an infinitive phrase, so the base pattern to + verb is the starting point. If you can identify infinitives quickly, you can also tell when a sentence is simply using an adverb normally and when the adverb is splitting the phrase.

### Prescriptive Grammar

Prescriptive grammar is where the traditional dislike of split infinitives comes from. It treats certain patterns as correct or incorrect based on usage rules, style, or authority. This is why some handbooks still warn against split infinitives, especially in formal writing or school grammar lessons.

### Descriptive Grammar

Descriptive grammar explains why split infinitives are now widely accepted in real English use. Instead of judging a form as wrong, it asks how speakers and writers actually use it and what effect it has. That perspective helps you see split infinitives as a normal part of English, not a broken rule.

### [double negatives](/english-grammar-usage/key-terms/double-negatives)

Double negatives and split infinitives are both common usage topics where prescriptive advice and actual language use can differ. Each one can trigger a strong "that sounds wrong" reaction, but the grammar question is more about context, meaning, and style than about a simple yes or no rule.

## On the AP Exam

A quiz question might ask you to identify a split infinitive in a sentence, choose the best revision, or explain why a sentence sounds more natural with the adverb inside the infinitive. In an editing task, you may compare "to quickly finish" and "to finish quickly" and decide whether the split improves emphasis or clashes with a formal tone. On a short writing response, you might be asked to connect the construction to prescriptive versus descriptive grammar. The best move is to name the structure, explain the effect on flow or clarity, and then justify whether keeping it makes sense for the sentence’s audience and style.

## Split Infinitives vs infinitive

An infinitive is the base to + verb form itself, like to run or to study. A split infinitive is a specific version of that structure where another word, usually an adverb, comes between to and the verb. If you can spot the base infinitive first, it becomes much easier to tell whether it has been split.

## Key Takeaways

- A split infinitive happens when a word, usually an adverb, comes between to and the verb in an infinitive phrase.
- The construction is controversial because prescriptive grammar has often discouraged it, while descriptive grammar accepts it as normal English use.
- Split infinitives are not automatically wrong, and many modern style guides allow them when they make a sentence clearer or smoother.
- You should judge a split infinitive by its effect in context, not by a rigid rule alone.
- In class, this term usually shows up in sentence analysis, revision questions, and discussions of grammar style.

## FAQs

### What is split infinitives in English Grammar and Usage?

A split infinitive is an infinitive with another word, usually an adverb, placed between to and the verb, like "to boldly go." In English Grammar and Usage, it is a usage issue that connects sentence structure with style choices. The main question is usually whether the split improves clarity or sounds awkward.

### Are split infinitives grammatically wrong?

Not usually. Many modern grammarians and style guides accept split infinitives, especially when they improve clarity or keep the sentence natural. Older prescriptive rules discouraged them, which is why the topic still comes up in editing and grammar classes.

### Why do writers avoid split infinitives?

Some writers avoid them because they were taught that split infinitives are incorrect or informal. Others avoid them simply for style, especially if the adverb sounds clunky in the middle of the phrase. But in many cases, keeping the adverb inside the infinitive is actually the clearest choice.

### How do I spot a split infinitive in a sentence?

Look for the word to followed by a verb, then check whether another word sits between them. In "to carefully explain," carefully splits the infinitive. If the sentence just has a regular adverb somewhere else, it is not necessarily a split infinitive.

## Related Study Guides

- [13.1 Defining Prescriptive and Descriptive Approaches](/english-grammar-usage/unit-13/defining-prescriptive-descriptive-approaches/study-guide/ELxnHIEtLbxt2uwI)

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