grammar.pronouns.subject-omission
Dropping subject pronouns
Spanish normally omits subject pronouns — the verb ending already says who acts. Keeping them adds emphasis or contrast.
grammarA1, A2v0.1.0
Explication
Hablo español already means 'I speak Spanish'; yo hablo español stresses the I. Use the pronoun for contrast (yo cocino y tú lavas), to disambiguate identical forms (él/ella/usted hablaba), or for emphasis.
Overusing pronouns is the classic English-speaker accent in writing: every sentence starting with yo sounds insistent or self-centered.
Exemples
Vivo en Montreal.
I live in Montreal.
I live in Montreal.
Région: global
Yo pago esta vez.
I'm paying this time.
I'm paying this time.
Région: global