1. Prepositions are words that express relations of place, direction, time or possession. Common prepositions include of, to, at, from, till, for, beside, against, up, down, and by. 2. Prepositions can appear alone or in conjunction with a noun phrase to form a prepositional phrase. A prepositional phrase functions as an adverb, indirect object, subject complement, object complement, or prepositional object in a sentence. 3. Examples of prepositional phrase functions include acting as an adverb with an intransitive verb, as an indirect object with a ditransitive verb, as a subject complement with an intensive verb, as an object complement with a complex