Every sentence needs a subject. The subject does the action in the sentence. The subject in a sentence must be a noun.
Look at these sentences. Each subject has been highlighted.
The dog wagged its tail.
Mom grilled hamburgers for dinner.
Our teacher showed a movie in class today.
In each of these sentences, the highlighted word is a noun – and each of these nouns is doing the action.
The dog wagged.
Mom grilled.
The teacher showed.
Here are more examples. Look for the subject that is doing the action.
Last night, a meteor streaked across the sky. meteor
My neighbors have a fire pit in their yard. neighbors
A squirrel ran across my lawn. squirrel
Every sentence needs a subject. The subject is always a noun and is always doing the main action.
▶ It’s your turn. Find the subject of this sentence. Three girls rang my doorbell. Did you find a noun that is doing something in the sentence? Good for you!