“Usted” is generally
more formal, while “tú” is a more formal use of the Word you. You would use
usted when referring to teachers, people of authority, and your elders, while
tú is more appropriate for friends and family members.
I think tú form ends in an s when you use it, such as “tú hablas”, meaning you
talk. It seems like the usted form just ends in the vowel of that verb, like in
the 3rd person, for example “usted habla”
If you are going shopping the least you can do is "anunciar una liquidación". This can be used for a brand or shop to communicate that prices are reduced so that would not depend on the buyer. The rest of the sentences correspond to the one who is buying or wants to buy.
Yo le digo la verdad a vosotros
