In English, an infinitive is a verb form that is the same as the base or dictionary form. A full infinitive (aka to-infinitive) is preceded by “to” (e.g., “to study,” “to run”), while a bare infinitive is not (e.g., “study,” “run”).
A split infinitive occurs when another word separates “to” from the verb in a full infinitive.
What is a split infinitive?
Full infinitives are also known as to-infinitives because they consist of “to” followed by the base form of the verb (e.g., “to jump”). A split infinitive is a full infinitive that has words (usually adverbs) separating “to” and the verb (e.g., “to joyfully jump”).
Is it okay to split an infinitive?
Grammarians have been debating split infinitives since at least the nineteenth century. In the 1800s, many (but not all) grammarians viewed split infinitives as ungrammatical, and a lot of schools began to teach this as fact. However, split infinitives are commonly viewed as acceptable and sometimes even necessary by modern grammarians and publications.
When to avoid split infinitives
Because some people still have a negative perception of split infinitives, it’s best to avoid them in academic or professional writing as long as the meaning or clarity isn’t affected.
When to use split infinitives
A split infinitive can be the clearest, simplest, most elegant choice without completely rewriting the sentence.
Frequently asked questions about split infinitives
What does it mean to split an infinitive?
Split infinitives have traditionally been viewed as ungrammatical, but nowadays they are largely viewed as acceptable and are sometimes necessary.
For example, in “the dentist told Geoff to always brush his teeth before bed,” moving “always” either results in an awkwardly worded sentence or makes it unclear: does “always” refer to how often the dentist tells Geoff or to how often Geoff should brush his teeth?
Is a split infinitive bad grammar?
Although split infinitives were traditionally viewed as ungrammatical, they are now largely viewed as acceptable and are sometimes necessary.
You may want to avoid them where possible in academic or professional environments, as some may still view them negatively, but you don’t need to avoid them entirely. Split infinitives can provide emphasis, and moving the adverb can sometimes result in an ungrammatical or unclear sentence.
For example, in “Gemma asked Kamil to quietly shut the door,” moving “quietly” either results in an awkwardly worded sentence or makes it unclear: does “quietly” refer to the volume of Gemma’s voice or the way she wants Kamil to shut the door?