what is an infinitive

An infinitive is a verb form that can function as a noun, adjective, or adverb in a sentence. It is formed by adding the word "to" before the base form of the verb, such as "to run" or "to eat". Infinitives can be used to express purpose or intention, as in "I went to the store to buy milk". They can also be used as the subject, direct object, subject complement, adjective, or adverb in a sentence. Infinitive phrases are groups of words consisting of an infinitive and any modifiers, objects, or complements that function as the actor(s), direct object(s), or complement(s) of the action or state expressed in the infinitive. For example, "to leave early" is an infinitive phrase that functions as an adverb in the sentence "I intended to leave early". Infinitives are an important part of English grammar, but their rules can be tricky.