Usted versus Ellos
Would I use Ellos or Ustedes for the following:
El doctor Gregorio y la doctora Elsa trabajan en la oficina de medicos.
El senor y la senora Valle ensenan en la universidad.
Los musicos tienen un concierto en la sala de conciertos todos los lunes.
Tu y Jorge necesitan practicar para el concierto.
2 Answers
Ustedes is the formal form of the second person of the plural (you). It is only used in South America, not in Spain. In Spain, the word ustedes is a reminiscent of the past, except in a few cities of the south, and we always use the form vosotros I am not sure if the use of "ustedes" in South America has another hints or if it use depends of any other variable, but for us (Spanish) it is useless.
To answer the question you asked in your comment, you use "ustedes" when talking TO more than one person. #1 and #2 are talking ABOUT more than one person. "Ustedes" means "you"; "ellos" means "they."