Does a sentence need subject?

Yes, a sentence generally needs a subject except in the case of imperative sentences.

Here's why:

* Subject-Verb Agreement: Sentences are built around a core structure of subject-verb agreement. The subject tells us who or what is performing the action, and the verb describes the action.

* Clarity and Meaning: A subject provides context and clarity to the sentence. It identifies the entity performing the action, making it easier to understand who or what is being discussed.

Examples:

* Complete Sentence: The cat slept peacefully on the couch. (Subject: cat, Verb: slept)

* Imperative Sentence: Go to the store. (No explicit subject; the implied subject is "you")

Important Note: Imperative sentences (commands or requests) often omit the subject because it is understood to be "you."

Let me know if you have any other grammar questions!