Yesterday I had someone ask me, "What is YOU FORMAL?" in Spanish? So, I thought I would give a quick explanation here for anyone else wondering.
YOU FORMAL is the verb form we use when talking to another person we do not speak to on a first name basis. This is a general rule of thumb, although it can vary a little from country to country in different cultures.
Examples of "formal" speaking would be a student talking to a teacher, talking to your doctor, talking to a police officer, etc.
So, if you are studying verb conjugations, you see that there is a form for "he/she/you formal". That is the verb form you use to speak "formally" TO that person.
If you are speaking to more than one person formally, you use the "they/you all" form.
Example using the verb "comer = to eat"
como = I eat
comes = you eat
come = he or she or you formal eat
comemos = we eat
coméis = you all eat (informal used in Spain only)
comen = they or you all eat
So, let's say you want to ask (in a formal way), Do you eat the tacos? You would say, ¿Come los tacos? or to a group, ¿Comen los tacos?
This does not exist in English. So, for us English speakers it takes a little getting used to.
I hope this helps anyone wondering, WHAT IS YOU FORMAL ANYWAY?