"Hi"
* Olá: This is the most common and general greeting, similar to "hello" in English.
* Bom dia: This means "good morning" and is used until midday.
* Boa tarde: This means "good afternoon" and is used from midday until evening.
* Boa noite: This means "good evening" or "good night" and is used from evening onward.
"Goodbye"
* Adeus: This is the most common way to say goodbye, similar to "farewell" in English.
* Até logo: This means "see you soon" or "until later."
* Até mais: This means "see you later" and is a more informal way to say goodbye.
* Tchau: This is a more informal way to say goodbye, similar to "bye" in English.
It's worth noting that the appropriate greeting or farewell will vary depending on the context, time of day, and formality of the situation.