* Prepositions are not statements. Prepositions are words that show the relationship between a noun or pronoun and another word in the sentence. They don't express complete thoughts.
* Statements are complete sentences. They have a subject and a verb and convey a thought.
Examples:
* Preposition: "on"
* Statement: "The book is on the table."
What might you be referring to?
It's possible you're thinking of a phrase that starts with a preposition. These are called prepositional phrases.
Example:
* Prepositional phrase: "on the table"
* Complete sentence: "The book is on the table."
Let me know if you can clarify your question.