Помогите с 4 заданием

1. When John arrived late for his exam he was upset because nobody had told him the time had changed.
2. The school team had never played in a real stadium before and they were excited to see so many spectators when they ran onto the pitch.
3. I was at a boarding school before I went to university so I knew how to look after myself, but some of my classmates had never been away from home and found it hard to manage without their parents at first.
4. Last Friday our teacher gave us a test in biology and I was able to answer the questions because I'd seen a documentary on the subject just a week before, not because I'd revised. In fact I'd forgotten that we had a test that day.