Subjective (grammar)

Subjective refers to the form of a noun or pronoun that is used when it is the main subject of a sentence, that means when it is the main thing performing the action.

Let's say you want to talk about a cat. If you are talking about the cat doing something, like "the cat is sleeping," then you would use the subjective form of the noun, which in this case is just "cat."

But if you want to talk about something being done to the cat, like "I petted the cat," then you would use the objective form of the noun, which in this case is "cat" with "-ted" added to the end.

Overall, subjective is just a fancy way of saying the form of a noun or pronoun that is used as the main thing doing the action in a sentence.