A split infinitive is a grammatic construct in which a word or series of words is placed in the middle of an infinitive. English is one of the rare languages with multi-word infinitives, and is thus one of the few languages in which split infinitives are possible.

Perceptive people will notice that the title of this node has, in fact, a split infinitive.

How to correctly split infinitives

In this sentence, "to split" is the infinitive. "Correctly" modifies the verb "split," and it's splitting "split" from "to." Got that?

Many grammar teachers tell their students to avoid split infinitives, and that's often good advice. Sticking words in there can make the sentence a lot harder to read. However, sometimes using a split infinitive is the best choice; try taking a look at two other ways we could have written this node title:

  1. How to split infinitives correctly
  2. How correctly to split infinitives

Examples (1) and (2) are grammatically correct by the letter of the law, but they read like crap. (1) separates the adverb "correctly" from the verb it modifies, and the reader is momentarily confused. (Is "infinitives correctly" what we're splitting?) (2) reads like a question — How correctly to split infinitives? How correctly indeed!

Here's another example. (No underlinings any more; the training wheels are off.)

  1. Steve decided to quickly run to the store.
  2. Steve decided to run quickly to the store.
  3. Steve decided quickly to run to the store.
  4. Steve decided to run to the store quickly.
  5. Steve quickly decided to run to the store.

The first example is a split infinitive, and Nos. 2-5 contain varying levels of ambiguity. (2) ought to mean the same thing as (1), but as the reader, are you sure "quickly" doesn't modify "decided"? In (3), "quickly" ought to modify "decided," but again it's not completely clear. (4) is a free-for-all; I'm not even going there. In (5), the writer's intention comes across clearly. We can say that (1) and (5) are the best ways to write the sentence, depending on what's being done quickly.

On the other hand, some split infinitives aren't necessary.

  1. Mary wanted to gracefully dance.
  2. Mary wanted to dance gracefully.
  3. Gracefully, Mary wanted to dance.

Ever gracefully wanted to do something? Me neither. In this example, there's no confusion about which verb "gracefully" modifies, so why use the split infinitive in (1)? Look at (3) — it's an awful construction that I would never endorse, but even there the reader is pretty sure that "gracefully" modifies "dance."

Now, as you write your own sentences, here's some rules of thumb.

  • Avoid the Monster Splits.

    1. By endorsing John McCain, I intended to willfully yet furtively swing the election to Al Gore.
    2. I took a deep breath, took off the pen cap and started to — I can't believe it's happening! — sign my name.

    Anytime you're splitting an infinitive with more than one word, stop and re-think things a bit — (1) could be written a lot better. And don't ever use punctuation within a split infinitive; (2) is ridiculous. Anyone who writes like that should be shot.

  • Split for emphasis.

    It's a famous example; why not use it?

    1. To boldly go where no man has gone before!
    2. To go boldly where no man has gone before. (shrug)

    You're Captain Kirk! You're bold! Split that infinitive! Don't be afraid! Push that "to" away from "go" and give Uhura some lip-to-lip mojo!

  • Dump the adverbs

    You'll note that many of my examples use an adverb as the "splitter" (i.e., boldly, quickly). Many adverbs are superfluous, so a simple solution to the split infinitive question is often just erasing the offending adverb altogether.

    Or, as Mitzi wrote to me in a /msg on July 15, 2002:

    (This reminds) me of a good piece of writing advice I received in college: as with accessories, adverbs should be used sparingly. For great effect (think sunbrowned skin bare of any adornment), write a piece and eliminate all adverbs after you've written it. The results are often muscular and more effective than "too many words".

    And you do want muscular prose, do you not?

    (The correct answer is, "Yes!")

  • When there's no good options, start over.

    1. I decided to ever so quickly run.
    2. I decided to run ever so quickly.
    3. I decided ever so quickly to run.
    4. I ever so quickly decided to run.

    (1) is a mess; is "ever" a verb? (2) is bad too; "run ever" looks a lot like "run over." (3) is a 50-50 proposition; flip a coin and figure out what it means. (4) makes the writer sound constipated.

    So what do we do? Try "none of the above." If you're the type of person that actually uses constructs like "ever so (adverb)," well, it won't kill you to write like a normal person once in a while.

High-five to m_turner for getting me started on this crazy grammar crusade.

For more on the wonderful world of split infinitives, check out these links:
  • The Slot: http://www.theslot.com/split.html
  • Bartelby: http://www.bartleby.com/64/C001/059.html
  • Logica: http://public.logica.com/~stepneys/cyc/s/split.htm

More from the chatterbox ...

wertperch says Regarding the "rule" to avoid splitting infinitives: "It is a bad rule, which many people (including good writers) reject. It increases the difficulty of writing clearly and makes for ambiguity by inducing writers to place adverbs in unnatural and even misleading positions." - Ernest Gower, The Complete Plain Words =)

So don't be afraid to split them infinitives, people!