Use the correct form of the words in brackets. 17. The play was a _____________________ success. (commerce) 18. Alexander Graham Bell ______________ demonstrated his invention. (success) 19. Can I leave the ______________________ of the tables for you. (arrange) 20. Alexander Graham Bell experimented with ways of transmitting _____________over a long distance. (speak) 21. The film ____________ is very attractive. (introduce) 22. The life in the countryside makes us relaxed because it’s very ________________. (peace) 23. She called him about her furniture ________________________. (deliver) 24. Each of my friends has a ____________ character. (differ) 25. You should do your test ____________ if you want to get good marks. (care) 26. There was still no ________________on what to do next. (agree) 27. This river is very _______________________ for swimmers. (danger) 28. My mother told me a very ___________________ story yesterday. (interest) 29. This old man is __________________ in one ear. (deafen) 30. He can play many kinds of ____________ instruments. (music)