I. Complete each sentence with the correct form of the word in brackets. In some cases you will also have to use a prefix. This will be either dis-, im-, ir-, mis-, non-, or un-

19. If you loose your cheque book, you should .........................  the bank without delay. (note)

20. It was a .................  letter addressed to the boss and the secretary shouldn’t have opened it. (confide)

21. The ........................  of the flight was delayed so we had to spend the night at the airport. (depart)

22. The teacher warned the children that if they .....................  again, they’d be punished. (behave)

23. It’s ..................  to study a language if you're never going to use it. (point)

24. I’m afraid I’m in the ..................  position of being out of work and heavily in debt. (envy)

25. Great works of art like Mona Lisa are ........................  (price)

26. I’m afraid you’ve .....................  me because that’s not what I meant. (understand)

27. Why do we always end up by having an ....................... ? (argue)

28. I’ve been a ...................  since I had a heart attack. (smoke)

29. Unless you ...................  I won’t forgive you. (apology)

30. I wish you’d be .................  instead of telling me lies. (true)

31. The weather in this country is so ....................  that you never know what to expect. (predict)

32. It’s a ....................  doing business with you. (please)

33. Although the stone in your ring looks like a diamond, I’m afraid it’s ....................  (worth)

34. How can you ................  the fact that some people live in mansions while others live in slums? (just)

35. It’s ...............  to expect to get something for nothing. (reason)

36. If you’re hoping to make a good .....................  you should pay more .............. to your ..............

.... (impress/attend/appear)