It is asking "What does your family do in the summer?"
To answer, you could say "En el verano, hacemos que ir a la casa de mi abuela."
(In the summer, we have to go to the house of my grandmother), or any other activity. You can put "en el verano" at the beginning or the end, or just not include it, but you would just state "we swim" (nadamos) or a simple answer like that.