Does aggiunge also mean he adds in the sense of he continues (to erite or tell or say). It's the same word in English, but it means something slightly different.
Yes, aggiungere means to add to something, both physically (e.g. aggiungere dell'acqua, add water) or metaphorically as in this case, adding to what she was saying or writing.
"She adds that she does not have sisters." how it can be correct, they put here have when if i use she i need to put has not have, is it an error or i don't understand something? can someone explain this to me, i know its the Italian language lessons but English its not my native language. thank you!
When using an auxiliary, in English as well as in Italian, only the auxiliary is conjugated while the main verb becomes infinitive; "she is" but "she can be", and "she knows" but "she doesn't know". In the same way in this sentence it could be "she has no sisters" or (with the auxiliary "do") "she doesn't have sisters". As you can see English and Italian form their negatives in different ways.
why not "le sorelle"? I have seen else where that you add the prepositions for family members and so on when it is plural and you don't add when it is singular?