Females say "Obrigada" and males say "Obrigado". The two words both mean "Thank you" but in different forms for either sex to use. And you can NEVER mix them. The same situation is also found in other Latin-oringed language.

Katherine, if you want to say "Thank you" in Portuguese, you can say just "Obrigado". If you want to say "Thank you so much", you can say it in Portuguese as "Muito obrigado".

Obrigado. muito means very much (i don't speak portugese lol).

You can say "Muito Obrigado" or just "Obrigado".

Thank you in portuguese is "Muito obrigado".