Bonsoir! can be considered formal or informal depending upon context. The greeting literally means "Good evening!" and tends to be more frequent in formal than in informal contexts. The pronunciation will be "bo-swar" in French.
"Salut" is an informal greeting in French, typically used among friends, family, or peers. It conveys a casual tone and is not suitable for formal situations. For formal contexts, it is better to use "Bonjour" or "Bonsoir."
"Bonsoir monsieur" is a formal greeting in French. It is used to address someone politely, typically in a professional or respectful context. The use of "monsieur" indicates a level of formality, making it appropriate for situations such as meeting someone for the first time or addressing someone in a position of authority.
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.