16.surprising　 17.mild　 18.volcanoes　 19. harbours; coast 20.seaside

Unit 19

11. voyage　 12.surface　 13.paragraph　 14.camping　 15. mainly

9.cattle; cattle　 10 possessions; possession

2.　　　 relation　　 4.import; export 　6.secretary　ference

1.　　　 surrounded　 3. wedding　 5.settled　　 7.percent　

1. bother　 2. promised　 3. experience　　 4. dishonest　　 5. extremely6. inspires/inspired　 7.optimistic 8. climate　 9. value　 10. threatened　 11. dull　 12 mean; generous 13.shelter14. kindergarten 15 graduation 16.bear 17.champion 18 bottom 19 regret 20. pianist

18Key

12.positive13.precious14.diamond15.lecture16.debts17.Mosquitoes18.francs19.lovely20.outline

Unit 16

1-10. comfort　 prove　 frame　 conclusion　 cruel　 shock　 views　　 advantage　 charge　 sharp　

11-20 experiment　 engine　 thunderstorm　 control　 liquids　 senses doubt gases　 conducted　 unnecessary

Unit 17

1.　　　tinue8.Besides9.outline10.worth11.author

1. honoured 2. fool 3. invitation 4. ancestors 5. generations6. faith 7. cycle 8. lighted 9. saluted 10. symbol　

ercial20. similar

Unit 15

1.energy 2. stomachs 3. ripe 4. paces 5. chemistry; chemical 6. now and then 7. keep up with 8. make a choice 9. digest 10. sleepy 11. soft 12. balance 13. tasty 14. boils 15. organic 16. diet 17. gained 18. function 19. mixture 20. suggestion

Unit 14：