We know that a noun acts as a subject in a sentence. The person or thing doing the action is the subject of the sentence.
Bob drives a truck.
Bob is the subject of the sentence. Bob is doing the action.
Nouns can also act as the object in a sentence.
The action happens to the object.
Bob drives a truck.
Truck is the object in this sentence. The action happened to the truck.
The subject does the action. Action happens to the object. We use a noun for both the subject and the object in a sentence.
▶Now it’s your turn. Find two nouns in this sentence. Mary baked a cake. Did you find one noun that is the subject, doing the action? Did you find another noun that is the object and has action happening to it? Good for you.