What defines the grammatical subject of a verb within a sentence?

The grammatical subject of a verb within a sentence is defined by the nominative case. In English grammar, the nominative case is used for nouns and pronouns that function as the subject of a verb. This means that when you are identifying the subject of a sentence, you look for the form of the noun or pronoun that is in the nominative case because it indicates who or what is performing the action of the verb or being described by it.

For example, in the sentence "She runs every morning," "She" is in the nominative case and functions as the subject of the verb "runs." The nominative case applies to both pronouns (I, you, he, she, we, they) and certain noun forms, making it crucial in identifying subjects in sentences.

Other options do not define the grammatical subject in this context. A possessive pronoun indicates ownership (e.g., "my," "yours") rather than the subject's action. A proper pronoun, which may quickly refer to a specific individual or entity, does not inherently indicate the subject of the action. An intransitive verb, while it may not require a direct object and simply expresses an action or state, does not define the subject itself