9. Four countries ____ __________ (visit) by John so far.
10. London ______________ (have) a population of eight million people.
11. Vietnam’s Independence Day __ ______________ (celebrate) on September 02nd .
12. We _ _____________ (visit) Sydney Opera House for several times.
13. Some activities ________ (prepare) to celebrate the lunar new year now.
14. When I came to the stadium, the match (start) _ ___
15. Before she (listen) _ ________ to music, she (do)__ _____ homework.
16. Last night, Peter (go) _ ___________________ to the supermarket before he (go) _________ _________________ home.
17. Most students (leave) __ ____________________ before the volcano (erupt) ________ _______________.
18. I (find) _________________ my pen after I (buy)__________ a new one.
19. Food and medical supplies (deliver)…… ……….yesterday afternoon.
20. In the future, natural diasters (predict)… … …………………… accurately with the help of technology.
21.Three cats (rescue) … ……………………….by the volunteers last Sunday.
22. Two houses (build) …… …………………….in the city every year.
23. The Earth (hold)… ………………………. by the gravity of the sun and orbits around it