54. Public transport will be used by the students in my school when travelling long distances.
55. The lights will be turned off when leaving a room or going to bed.
56. The report won't be finished until my father comes.
57. A lot of money will be used on building the school.
58. The use of biogas for cooking will be increased by people in the countryside.
59. This room will be painted by students next month.
60. A dam for hydroelectricity will be built in this area.
61. Viet Nam has less population than China.
62. A big city has more jobs than the countryside.
63. Hoa has fewer old stamps than Lan.
64. I have never come to a big city before.
65. Minh is the tallest boy in my class, isn't he?
66. Your parents don't live in the countryside, do they?
67. Mai has studied English for ten years, hasn't she?
68. I'm old enough to join the club, aren't I?
69. There are many problems in a big city, aren't there?