29. Respiratory

30. Persuasive

31. Increasingly

32. Suggestions

33. Movement

34. Interactive

35. There was an increased demand for travel, so the government decided to invest in building the metro system.

36. How about making posters on saving energy and hanging them around the school yard?

37. He worked so hard that he made a success of his business.

38. A mechanic has just repaired my neighbor's car recently.

39. A girl who chatted on the internet with me two months ago is mysterious

40. I am better at my written English than my spoken English.