"¡Hasta luego, Paco!" is an informal expression. The use of "Paco," a familiar name, indicates a casual relationship, making it suitable for friends or acquaintances rather than in formal settings. In formal situations, one might use a more respectful address, such as "Hasta luego" without a first name or using a title.
No puedo esperar a vivir contigo (informal)/con usted (formal) -or- No puedo esperar hasta que yo vive contigo (informal)/con usted (formal).
"Hasta luego" is neither formal nor informal, it straddles the middle between them and can be used in most situations. If you want a truly formal way of saying goodbye, "Adios" is probably the most formal. "Chao" correspondingly, should only be used between close friends or family members who are your age or younger.
it is an informal group
formal is the cinema and informal is a gay man
It's both formal and informal. It depends on how you say it. If you say "Adiós, señora." it's formal. If you say "Adiós, amigo." it's informal.
informal
formal and informal rhythm
what is formal and informal communication
formal
Formal is polite, informal is rude and obnoxious.
There is no formal slang. Slang is informal language.
what is formal and informal shareholders agreement