You would use "Usted" or "Ud."
It depends on who you are talking to. Spanish verbs are conjugated differently when the subject is considered either formal or informal to the speaker."Necesitas Algo?" should be used if you are speaking informally, like to a child, employee, or friend."Necesita Algo?" should be used if you are speaking to an employer, a parent, someone older than you, or a stranger.
Informally, it would be "tu hermanastra." In a formal context, or when speaking to a stranger or someone older than you, etc., it would be "su hermanastra."
Thou is an older version of you, and you is a pronoun, therefore, Thou is a pronoun.
"Heself" is a reflexive pronoun. It is a non-standard and archaic form used in some dialects or older texts, where "he" would be the subject pronoun and "himself" would be the reflexive pronoun.
Portuguese is considered older than Spanish. Portuguese can be traced back to the Latin language brought to the Iberian Peninsula by the Romans, whereas Spanish developed later from Vulgar Latin in the northern regions of the peninsula.
Vous avez..... ? (for a stranger or someone older than you) or Tu as..... ? (for a good friend)
"or older" (talking about a living being) = o yotehr yashen (או יותר ישן)"or older" (talking about an object or city) = o yotehr atik (או יותר עתיק)
Formal means that you are talking to someone older than you or someone you would show respect to. Examples are ¿Como se llamas? you are asking someone like a child or someone your age what their name is. ¿Como te llama? is asking the same thing but you would use it when talking to someone older than you, or who is in a higher position than you are.
English is older than Spanish. The English language developed around the 5th century AD, while Spanish started to evolve during the 9th century AD from Latin.
Arabic
Latin is an older language than Spanish. Latin was the language of the Roman Empire and eventually evolved into several Romance languages, including Spanish.
To a stranger/someone older: You love him = vous l'aimez To a good friend: You love him = Tu l'aimes