1.Half an hour had gone by, but the last bus hadn't come yet. We had to walk home.
2.Mary looks worried about the Chinese exam, because she hadn't learnt the text by heart.
3.Since the basketball match has been postponed, we may as well visit the museum.
4.He lived with his parents in Australia all the way through the Second World War.
5.Since I graduated from Nanjing University in 1985, I have kind of lost touch with my classmates.
