theinfinitive

theinfinitive is a term used in grammar to denote the infinitive, a non-finite form of a verb that is not marked for tense or subject agreement. It commonly serves as a citation or dictionary form and often functions as a noun, an adjective, or an adverb within larger sentences.

In English, the infinitive is usually formed with to plus the base verb, as in to walk or to read. A bare infinitive omits the particle to, as in walk or read, and it appears after modal auxiliaries (can go, must leave), certain verbs of perception or causation (make him go, let her speak), and in some causative constructions with have or get. The infinitive can introduce subordinate clauses expressing purpose (I came to discuss), intention (I am here to help), or obligation (It is necessary to learn).

The infinitive can also function as a noun, as in To err is human, where the clause itself acts as the subject. It is common in sentences with an adjective or noun that governs a following infinitive, such as eager to please or the decision to move. The to-infinitive may be contrasted with the -ing form (the gerund or present participle) in certain syntactic and semantic contexts.

Split infinitives—placing an adverb between to and the verb—are a traditional point of style debate. Modern usage generally accepts split infinitives when they improve clarity or natural flow.

Cross-linguistic note: many languages use infinitive-like forms with distinct endings or particles. Some languages have a purely non-finite infinitive that is not marked for person or number, while others rely on different non-finite constructions.