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Changing Cities
• By the year 2050, 66% of the people on Earth will live in large cities. Most of them will live in tall apartment buildings, so it makes sense to design those buildings in ways that are good for the environment. Rooftop gardens, for example, save energy for heating and cooling and are a comfortable place for people to spend time.
• Crossing the street in a big city can create problems. One solution is the "X-crossings" found in Tokyo, Japan, and other cities. There, when the traffic light turns red, all of the vehicles must stop. Then, the pedestrians can cross in any direction. Another solution could be neighborhoods with more stores and restaurants on every block. This makes it easier for people to walk to the places they need to go.
• In the future, many cities will have many kinds of public transportation, like Hong Kong. In addition to cars and taxis, people in Hong Kong use buses, trains, boats, and streetcars all convenient ways to get around the city.