This document provides examples of using prepositions of place such as "in", "on", and "under" by asking "Where is/are X?" and providing the answer with the preposition and location. Some examples include "Where is the boy? He's under the tree", "Where are the penguins? They're on the ice", and "Where are the books? They're in the backpack". It concludes by providing a link to a YouTube channel for English language learning.