Here's how it works:
* Subject: The person or thing performing the action of the verb.
* Nominative case: The form of the noun that is used for the subject.
Example:
* The dog barked at the mailman. (Dog is the subject of the verb "barked" and is in the nominative case.)
Note: In English, nouns generally don't have distinct forms for different cases like in some other languages (e.g., Latin, German). We primarily determine the nominative case by the noun's position in the sentence and its role as the subject.
Let me know if you'd like more examples or want to discuss other noun cases!