Ответ:

  1. Roby: I’m not sure. I’ll let you know this afternoon.
  2. Marcus: I know, I’ll put some on the shopping list.
  3. Issy: I’ll have the blue ones, please.
  4. Emily: I’m going to visit my cousin in the USA.
  5. George: OK, I’ll close the window.
  6. Barry: Yes, I’m going to study all morning!

Правило: решения, предложения и обещания — will; заранее запланированные действия — be going to.