Eight years ago,officials in Chicago,Illinois,decided to replace the black roof on the city government building with a planted garden.The aim was to reduce energy costs,improve air quality and control the rainwater entering the city’s waste system（系统）.Green roofs also help reduce a problem called urban heat islands（城市热岛现象）.During hot weather, the building’s roof could reach temperatures of up to 76℃.With the garden,the temperature of the roof area was reduced by at least 30℃.Workers planted over 150 kinds of plants that could stand bad weather.Now,the area is cooler,the building requires less energy to keep cool,and the roof looks nice.Chicago also offers money to help people pay for building their own green roofs.
About five years ago,officials in Thane,India,decided to reduce the city’s depending on power from coal.The city often experiences lack of power because of the large numbers of people using electricity.Officials decided to save energy by putting water heaters（热水器）powered by the sun on top of the city’s main hospital.The hospital saved thousands of dollars in energy costs each year.Officials then began building this kind of water heater around the city.
China has announced plans to build a city called Dongtan.The company designing the city Says it will produce its energy from the wind,from the wind,sun and waste.The aim is for the city to be an example to the rest of China.
40.What did the officials in Chicago decide to do?
A.To grow plants on the roof of the government building.
B.To made use of the rainwater in the city’s waste system.
C.To improve the air quality of the city greatly.
D.To build another government building
41.What problem does Thane have according to the text?
A.The city doesn’t have enough electricity for its people.
B.The city’s main hospital lacks money for energy costs.
C.The city needs more water heaters for its people.
D.The city needs to control its population growth.
42.Why does China plan to build the new city?
A.To set an example of using clean energy.
B.To provide energy for the rest of China.
C.To learn how to use new energy forms.
D.To gain experience in city design.
43.What does the author try to tell the readers about?
A.Problems in big cities of the world.
B.The rising energy costs in cities.
C.Different ways of going green.
D.Energy problems in the world.
C
On my way home from work one day in 1994,I stopped at a supermarket
