53. He s____________ in paying off the debt after 10 years of hard work.

52. You should take the medicine a_____________ to the instruction.

51. Whoever wants to join us must o_________ the rules.

50. The climate is mild t_____________ the year.

49. Whether we can go camping d____________ on the weather.

48. Jackie Chan is a w____________ film star.

47. As she ate more than necessary, she was putting on w___________.

46. We can protect the environment by r____________ waste gas from cars and factories.

45. His speech was so a______________ that no one noticed the time.

44. Waste gas is h____________ to our health.