Meaning: This means there is a cat sitting on a mat near a door.
Choice of Words: Cat is a common household pet. Sit is an action that involves resting in a position. Mat is a piece of material that is placed on the floor. Door is an opening in a wall or fence. Near is a preposition that describes the location of something. When you put them together, "Cat sits on mat near door" describes the action of a cat sitting on a mat near a door.