PRONOUNS FOR EMPHASIS
Because Latin verbs use the endings to show who the subject is, they don’t need a separate pronoun like English uses. (e.g., I walk, you walk, we walk) But Latin pronouns like ego, tū, and nōs still exist! Why? They are used for emphasis, to give a bit more attention to the person who is the subject. Try saying each example aloud with an added emphasis on the pronoun.
Scrībit celeriter, sed ego scrībō bene.
He writes quickly, but I write well.
Tū nārrās historiam.
You are telling the story.
Compare with: Historiam nārrās.
You are telling the story.