Ответ:

  1. I've got a flute and a saxophone. I can play the flute, but I can't play the saxophone.
  2. I've got some rabbits and some goldfish. The rabbits' names are Floppy, Blackie and Fred. The fish's name is Goldie.
  3. At home we've got an old piano and some drums. The piano is in the living room and the drums are in my brother's bedroom.
  4. We've got some computers and an interactive whiteboard in the classroom. The computers are old, but the interactive whiteboard is new.

Артикль a/an употребляется при первом упоминании одного предмета, some — с неопределённым множественным числом, а the — когда предмет уже упоминался или является определённым.