What does a preposition indicate in a sentence?

A preposition indicates the relationship between the subject and another word in a sentence, particularly showing how they are connected in terms of location, direction, time, or other abstract relationships. For example, in the phrase "The cat is under the table," the preposition "under" illustrates the spatial relationship between "the cat" and "the table." This function of prepositions is essential for providing clarity and context in sentences, helping to explain where, when, or how something happens in relation to other elements within the sentence.

The other options refer to different grammar concepts: the action performed by the subject pertains to verbs, the main theme of the text relates to the overarching message or central idea, and the order in which events occur relates to sequencing or narrative structure. Thus, they do not correctly reflect the role of prepositions in sentence construction.