The feedback says:
Correct solution: You can be a teacher. You used the past tense "could" instead of the present tense "can".
"Could" can also be present tense, implying ability or capacity. "You could be a teacher" is correct, because it means "you have the ability to be a teacher, should you choose to do so".
No, these are not really the same. Could expresses the conditional mood in English when used in this way. Pode does not represent the conditional in Portuguese, poderia does. "Se ganhasse a lotaria, compraria um carro novo." "If I won the lottery, I'd buy I new car." Or.. "Se ganhasse a lotaria, poderia comprar um carro novo." "If I won the lottery, I could buy a new car." Their explanation is poor, but their correction is ultimately right.
Thanks a lot. We have not got to "poderia" yet in this course, but your explanation makes sense.