Split Infinitive Grammar Rules and Tips

Updated September 23, 2020
split infinitive example
    split infinitive example
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You may have heard that you’re not supposed to split infinitives when writing. But how do you know when you’re splitting infinitives, and how do they impact your writing? Keep reading for grammar rules and tips regarding split infinitives, as well as how to fix them.

Definition of a Split Infinitive

An infinitive is a combination of “to” and another verb. It’s a verbal phrase that can be used as a noun, adjective or adverb.

Examples of infinitives in sentences include:

  • Juan played his guitar to entertain the audience. (used as an adverb to modify played)
  • Today is a great day to go to the beach. (used as an adjective to modify day)
  • I only want to talk to you. (used as a noun)
  • We ordered a pizza to share with the family. (used as an adverb to modify ordered)
  • The rain ruined my plan to tend the garden. (used as an adjective to modify plan)

A split infinitive occurs when you place a modifier (usually an adverb) between “to” and the verb. It looks like this:

  • Juan played his guitar to expertly entertain the audience.
  • Today is a great day to finally go to the beach.
  • I only want to quickly talk to you.
  • We ordered a pizza to generously share with the family.
  • The rain ruined my plan to carefully tend the garden.

These sentences might sound right when you read them out loud. However, if you have a traditional teacher or editor, be prepared to see a lot of editing in your sentences with split infinitives.


Split Infinitive Rules

Traditionally, grammar students were always taught not to split their infinitives. The rule dates back as early as the Victorian Era, when Henry Alford advised against splitting infinitives in his 1864 book The Queen’s English. Strict grammarians also dislike split infinitives because they interrupt the unit of thought – the infinitive – with a modifier. It separates “to” from its verb, which can make the sentence confusing.

Style guides from the 20th and 21st centuries don’t directly speak out against split infinitives. However, they do advise writers against awkward sentence construction that often includes splitting infinitives. The general rule in English is to avoid splitting infinitives if you can.


How to Fix a Split Infinitive

If you’re scanning your work and finding split infinitives, don’t worry. Fixing split infinitives is usually a matter of rewording your sentence. You can move, remove or change adverbs to maintain the sentence’s meaning but also avoid split infinitives.

For example:

  • split infinitive - Harry tried to quietly turn the doorknob.

    fixed - Harry quietly turned the doorknob. (Changed the infinitive to a past-tense verb)

  • split infinitive - This is the truck I hope to someday buy.

    fixed - This is the truck I hope to buy someday. (Moved the adverb)

  • split infinitive - We expect our profits to completely double in the next quarter.

    fixed - We expect our profits to double in the next quarter. (Removed the adverb)

  • split infinitive - Heather promised to always love her husband.

    fixed - Heather promised to love her husband forever. (Changed and moved the adverb)

  • split infinitive - My mother began to delicately pick up the broken glass.

    fixed - My mother began to pick up the broken glass delicately. (Moved the adverb)

Some of these sentences are more awkward than others. But if you’re trying to eliminate split infinitives, following these tips can clean up your writing and help you communicate even more clearly.


Are Split Infinitives Ever Okay?

There are some instances in which split infinitives are acceptable – and even preferred. That’s because spoken language and written language don’t always agree on what sounds better. A non-split infinitive looks better on paper, but can sound odd when spoken aloud.

For example, examine the sentence from the examples above:

Today is a great day to finally go to the beach.

The adverb “finally” splits the infinitive “to go.” But is there a better place in the sentence to put the adverb? Read these corrections out loud:

  • Today is a great day to go to the beach finally.
  • Today is a great day finally to go to the beach.
  • Today is a great day to go finally to the beach.

“To go” is intact in each correction, which might make an editor happy. But each sentence now sounds awkward, so splitting the infinitive makes the most sense. Written language rules have caught up to spoken language rules in these cases. Try it in your own word processor – your autocorrect feature will agree that splitting the infinitive is the best approach!


Common Split Infinitives

Now that you know how to identify split infinitives, you’ll find them everywhere. Take the quote “To boldly go where no one has gone before...” from Star Trek. Wouldn’t it sound odd to change the sentence to “To go boldly where no one has gone before...”?

Some common split infinitives include:

  • to better understand
  • to really love
  • to secretly plan
  • to thoroughly clean
  • to always avoid
  • to suddenly notice
  • to completely respect
  • to actually fit
  • to finally arrive
  • to wholeheartedly approve
  • to warmly welcome

If you’re still confused about whether to keep or fix a split infinitive, read it out loud. Then fix it and read it again. Which one sounds better? Chances are, you’ve solved your problem already.


(Some) Grammar Rules Are Made to Be Broken

You’ll find that many people still feel strongly about split infinitives, while others don’t mind them as much. And in many cases, split infinitives are actually the best grammatical choice. Check out six more grammar rules you can break in your writing (as long as you know what you’re doing).