A preposition leads to an object, which is the part of the sentence that receives the action of the verb. The preposition also tells how the object is related to the rest of the sentence. The couch is the object, because it receives the action of the verb—the walking. The preposition, across, tells how the couch is related to the rest of the sentence. It links the fact that the cat walked with information about where it walked: across the couch. Prepositions can help show not just where something took place, but how and when. Besides the ones listed above, some common prepositions are about, after, among, between, beyond, but, despite, during, for, of, since, through, until, and without. See also: Prepositions: Good Things Come in Small Packages and Prepositional Phrases: The Big Daddy of Phrases.
