What is the main function of a preposition?

The primary function of a preposition is to connect a noun or pronoun to another word within a sentence, establishing a relationship between different elements. This relationship often provides crucial information regarding direction, location, time, or means. For example, in the phrase "The book is on the table," the preposition "on" connects the noun "book" to another noun "table," indicating where the book is located. Understanding how prepositions work helps in creating clear and coherent sentences, as they serve to clarify the relationships between the people, places, or things being expressed.