С, . the water in this lake (look) very clean. 2. maths (not/interest) me very much. 3. all of our furniture (be) brand new. 4. sugar (damage) your teeth. 5. the news they brought us (be) good. 6. your trousers (not/match) your shirt. 7. the team (discuss) strategy before every game. 8. chickenpox (give) you an itchy rash. 9. billiards (be) his favourite game. 10. knowleadge of other languages (help) people in business. 11. ten minutes (be) too little time to finish this report. 12. the staff (be) happy with the pay-rise. 13. physics (be) my favourite subject. 14. your bathroom scales (be) not very accurate. 15. table-tennis (be) sometimes reffered to as ping-pong. 16. the scissors (cut) very well. 17. mumps (be) contagious. 18. these trousers (be) terribly unflattering. 19. the rubbish (have) been taken away. 20. most people (worry) about the effect of pollution on the environment.
2. does not interest
3. is
4. damages
5. were
6. do not match
7. discusses
8. gives
9. is
10. helps
11. is
12. is
13. is
14. are
15. is
16. cut
17. are
18. are
19. had
20. worry