Answer:
I think it is necessary.
Explanation:
Without the "a" it's like you're asking a question, when you add the "personal a" you're saying it as in you did that!
It is incorrect. The correct way would be "el pato volo a su casa"
16. Departamento
17. Comedor
18. Sala
Option 1: because its in past tense "she BOUGHT clothes last friday"
