The document is a telephone conversation.
Jack has gone* to Australia for 6 months to study. He is calling his mum in Bristol (in Britain). He is telling her about his experiences and opinion.

* He has been* to Sydney and he has visited the opera house. He thinks it is fantastic. For him, Sydney is the coolest city he has ever visited.

* He has travelled a long trip to the outback. Uluru is the most beautiful site he has ever seen*. He thinks it's gigantic. He has spent* a great time.

* He has met* aboriginal artists. He is enthusiastic about their art. It's the most unusual way of painting he has ever experienced.