Definition: Infinitives are adjectives used to modify a noun or pronoun, as in "His infinte enthusiasm for science." They are derived from the infinitive prefix "in-" which means "to" or "by." The basic idea behind using infinitives is that they allow us to change the meaning of a word by modifying it. For example, instead of saying "He drives a car," we can say "He drove a car." In English, there are three types of infinitives: active, passive, and participial. Active infinitives have a verb with them; they modify verbs like "to drive" or "to take." For example: - He walked to the store. - I was walking to the store. Passive infinitives don't have a verb with them; instead, they use adjectives (such as "big," "beautiful," or "happy") and other adverbs (like "very" or "slowly"). They modify noun phrases like "he is reading books" or "she walks quickly." For example: - I read books. - She walks quickly. Participle infinitives are those that have a verb with them and no adjectives or other modifiers: they modify the subject of another sentence by adding meaning to the subject. For example, we can use participle infinitives like "ran," "slept," or "walked": - He ran quickly. - She slept soundly. Infinitive verbs are usually used in a few specific contexts: - Adjectives: "He has long hair" and "She is tall." - Nouns: "I have two daughters." (This sentence is adverbial, meaning it modifies the subject, not the verb.) - Prepositional phrases like "he walks quickly to the store," or "she runs fast to school." (In these cases, the preposition "to" modifies the action of walking) - Adverbs: "He is a happy boy" and "She is so tired." Infinitives are an important tool for grammar. They help us make sentences more clear and effective by changing their meaning from one sentence to another.

infinitive