"Sa" is not a word in Spanish, so it is not anything.
It is "pon". Example: Pon la silla en la mesa. "Put the chair at the table".
ven
The affirmative ustedes command of pagar is "paguen."
This can be a little confusing. The form you are speaking of is "sé", which is identical to the first person indicative. To tell the difference, you must have context.
If it is Tu for ......... Me: Tu Go: Ir 2: Dos
An affirmative "tu" command is what is used to tell a person you are familiar with to do something. Examples include: ¡escucha! (listen!), ¡espera! (wait!), and ¡mira! (look!).
tu as 2 frères (affirmative)
Levántese
Tu quiere ir para escuela = You wanna go to the school.
Puedes derek ir con tu?
Levántese