Best Answer - Chosen by Voting
Greeting:
Bom dia = good morning
Boa tarde = good afternoon
Boa noite = good evening/good night
Olá/oi = Hello/hi
E aí? = what's up? (rather casual)
Asking how the other person is:
The most common way is:
- Tudo bom? (The answer might be "tudo bom?" as well)
But you might hear these ones as well:
- Tudo bem?
- Como está? (rather formal, I believe)
Answering the questions above, respectively:
- Tudo, e você/tu? / Tudo, e contigo?
- Tudo bem, e você/tu? Tudo bem sim, e você/tu?
- Estou bem, obrigado. E você? (this sounds more formal!)
"What about" in Portuguese is "e...?"
So for example, what about your family would be "E a sua/tua família?"
I hope that helps. ^^
