Infinitive markers are function words that distinguish the base forms from the infinitive forms of English verbs. Function words are words that perform definite grammatical functions but that lack definite lexical meaning. Only one grammatical form can perform the grammatical function of particle in the English language: the p-word to.
Similar in form to the preposition to, the p-word to no longer performs a prepositional function but instead functions as an infinitive marker with infinitive verb phrases. The base form a verb is the dictionary entry form of the verb. The base form is identical in form to the simple present form of regular verbs in the first person, second person, and third person plural. For example:
Note that the base form of the only irregular English verb in the simple present is be.
The p-word to functioning as an infinitive marker distinguishes the base form from the infinitive of English verbs. For example:
- Base Form – Infinitive
- jump – to jump
- crawl – to crawl
- watch – to watch
- pickle – to pickle
- be – to be
Although contrary to prescriptive rules, split infinitives are grammatically acceptable in Modern English. A split infinitive occurs when another word, usually an adverb, separates the p-word to functioning as an infinitive marker from the verb, thus splitting the infinitive. For example:
- to boldly go
- to quickly leave
- to not care
- to more than triple
The p-word to performs the grammatical function of infinitive marker within infinitive verb phrases in English grammar.
Brinton, Laurel J. & Donna M. Brinton. 2010. The linguistic structure of Modern English, 2nd edn. Amsterdam: John Benjamins Publishing Company.
Hopper, Paul J. 1999. A short course in grammar. New York: W. W. Norton & Company.
Huddleston, Rodney. 1984. Introduction to the grammar of English. Cambridge: Cambridge University Press.