Here's why:
* Prepositions show the relationship between a noun or pronoun and another word in the sentence.
* They often indicate location, direction, time, or possession.
For example:
* "The book of fairy tales" - "of" shows possession.
* "The cat sat on the mat" - "on" shows location.
* "He left before noon" - "before" shows time.
Let me know if you have any other questions!