8 Make the sentences interrogative.
1. Had Mary booked the tickets before?
2. Had we been to this exhibition?
3. Had you received the invitation before Wednesday?
4. The bus arrived before 5 o'clock?
5. Had Tom heard that story before?
6. Had they gone to the railway station before 6 o'clock?
7. Had my father returned from his business trip by the weekend?
8. Had we met Eric before the lesson?
9. Had the taxi come by 7 o'clock?
10. Had they used this key before?