题目内容：

    In English-language news, when you read about "relations between Beijing and Washington", it actually means "relations between China and the US". That's how important capital cities are -they stand for the country. The capital city has many roles. It is home to the central government as well as a center for cultural and economic activities. However, capital cities usually have a large population, which can be a big problem.

In August, 2019, Indonesia said that it will build a new capital on the island of Borneo. One of the reasons for this is that Jakarta, the current capital, is overpopulated. In Jakarta, the traffic is heavy and the areas people live in are crowded. What's worse, the ground has been going down at an average rate of about 10 centimeters a year and in some northern parts the ground is already 2 to 4 meters below the sea level. Rising sea levels linked (关联) to climate change could make the problem even worse in the future.

Last century, Rio de Janeiro, the then capital of Brazil, was overpopulated as well. In 1960, the country moved its capital to Brasilia to solve this problem. People believed that if they moved the capital to a less-developed city, Brazil would have more balanced development. This turned out to be right.

Many capital cities are facing problems as they develop. Besides building a new one, maybe new technology can help solve some of the problems.

Beijing In 2015, China's government called for building "smart" cities and planned to turn Beijing into one of these cities. A new sub-center in the city's Tongzhou district will be the testing ground for this idea. "Smart" technology will be used to solve traffic problems, control air pollution and recycle garbage.

Tokyo The capital of Japan is working to make itself a "green" city. People are encouraged to plant trees on their rooftops. The city will use technology to recycle rainwater and turn a landfill into a forest.

Singapore Singapore is a city-state. It is using internet of things(物联网）technology to help save energy. In public housing, smart sensors (传感器) remind people of how much water and electricity they are using.

1.With the example of Brazil, the writer tries to tell us that         .

A.it can be a good choice to move a country's capital

B.Indonesia can move its capital city Jakarta to Brazil

C.it is right for every country to change its capital city

D.most capital cities usually have a large population

2.What can we learn from the passage?

A.Capital city can represent all the roles of the country.

B.Water will cover the current capital of Indonesia soon.

C.Beijing has solved many problems by using technology.

D.Both Japan and Singapore are working to save energy.

3.The passage mainly talks about _______.

A.how to use new technology smartly B.how to solve the problems of capital cities

C.what the problems of capital cities are D.what the relationship between capital cities is