Решение:
Надо поставить глаголы в скобках в Present Perfect.
- She has sailed solo around Britain twice and is planning to sail to Iceland soon.
- They have flown in a helicopter over New York and say it is an amazing experience.
- We have driven quad bikes on the highlands in Scotland once and we loved it.
- He has already ridden a camel in the desert and would like to try riding an elephant through a jungle.
- Anton's dad has travelled across Alaska on a dog sled. He's a real adventurer.
Ответ: has sailed, have flown, have driven, has already ridden, has travelled.