Краткое пояснение: Используем 'has' для третьего лица единственного числа (he, she, it) и 'have' для остальных лиц и множественного числа. Выбор зависит от подлежащего в каждом предложении.
Ответ:
- 1. They have already planned their trip.
- 2. He has always been a risky person.
- 3. She has never seen lions alive.
- 4. Stella and John have learnt a lot about ancient culture.
- 5. Tim and Tom have never travelled by boat.
- 6. We have never seen old castles.
- 7. He has just finished reading a book about travel to Africa.