17. This is the first time I __________ the experiment on plant breeding. A. have done B. do C. would do D. did 18. I have been invited to a wedding __________ 14 February. A. in B. of C. on D. at 19. When I saw him, he _____ a black suit. A. wore B. was wearing C. wearing D. wears 20. Your car is different _____ mine. A. to B. in C. from D. for 21. I found history very _____. A. amusing B. amused C. amuse D. to amuse 22. Her _____ include swimming and reading. A. interests B. interesting C. interested D. interest 23. Great Opera _____ of the world can be heard at the Sydney Opera House. A. sing B. singings C. singers D. to sing 24. English is the _____ language on one- fifth of the land area of the world. A. office B. official C. officer D. officially 25. English tends towards _____. A. simple B. simplicity C. simplier D. simply 26. He looks _____ today than yesterday. A. good B. well C. better D. goodly 27. There is a _____ difference between the north and the south. A. region B. regional C. regionally D. regioner 28. He went to a seaside resort because he was keen on _____. A. windsurf B. windsurfing C. to windsurf D. to windsurfing