"I'm sorry, I do not speak Portuguese."
Translation:Lo siento, yo no hablo portugués.
Ha! I see your point, but I guess Lo siento is not always used as seriously as the literal meaning!
I'm not very experienced with Spanish, but I think of perdon more like "pardon me" (for interrupting you while you're busy), and disculpe meaning more like some American slang, "My bad!" - (what an Am. Football kicker says when he hangs his head and pats his chest indicating he blames himself, and it's all his fault, for missing the winning Field Goal).
Disculpe reminds me of the words "culprit" and "culpability," both setting BLAME. (Just my opinion about the nuances.)
For "pardon me" for interrupting you while you are busy, it would be "disculpe" (used to call someone's attention).
Disculpe is also used to ask for a permission.
When "lo siento" means "I'm sorry" (even for a mild offense), it's used for apologizing.
Perdón is stronger than "lo siento", but used the same way, to apologize about something, to say "sorry".
Bumping into someone, you would use "lo siento" (I am sorry/ I apologize for this).
Correct: “Perdón” or “Perdona” or “Lo siento“.
Not “Disculpe” in this case.
"Disculpe" is used to attract someone's attention.
Or for asking a permission.
Yes, generally a mild offense.
(However, we could imagine cases where it's a matter of death or life, if the person is sick, and tries to explain their problem.)
But even in Duolingo sentence we have here, "lo siento" is okay, because it can be applied to a mild offense.
Disculpe - you use it to call someone's attention, for example an employee in a store or you can also use "permiso", "Disculpa/permiso, ¿me puede decir dónde están las cámaras?" you also use permiso when you need to pass and there are people in the way.
Perdón/lo siento - This ones are for apologizing, perdón is basically the same thing as lo siento but with a heavier tone. You step on someone's foot you say "ay! perdoneme/perdoname" or "lo siento/ lo siento mucho!".
Disculpe is not only used to attract someone's attention, but also to ask for a permission.
But: Disculpe is not used to apologize, or to say "I'm sorry" (about something).