Before this sentence there was almost same example without using "ao" (for ex. paga o homem). In this case, which one is true?
Both. It has few changes in meaning...
...pagamos o homem OR ...pagamos ao homem (ao=para+o)
...pagamos a mulher OR ...pagamos à mulher (à=para+a)
You need to specify the direct object if you want to use this construction. Ex. I paid money to the man.
Shouldn't the translation be: Finally we paid the man. !? Using finally puts the action (to pay) in the past.
It could be also since pagamos can be used in the past or in the present. Terrible choice for this example...
why for the preposition "a" here? "to pay" goes generally with simple accusative...
pagar + noun = pague o boleto no banco. pagar + a + someone = pague Ao Carlos o que lhe deve.
Another sentence in this lesson is exactly the same, but without the "a." Was that a mistake?
it's dative -- ao homem is the indirect object, implying an unstated direct object (the money, the bill…).
In this same lesson I used "paid" - now suddenly that's wrong and "pay" is the right answer. As leomilrib says, both are correct. Please fix it!
'Finally we paid to the man'- Is it incorrect? Pagamos can be used either in presente or Pretérito perfeito. In Pretérito perfeito, both spellings are considered to be correct- pagámos and pagamos.