题目内容：
根据材料回答题：Forests for Cities
You are standing in a beautiful forest in Japan。The air is clean and smells like plants and flowers． There are l75 different kinds of trees，and 60 kinds of birds live here．___________(46)You are downtown in the city of Nara，Japan，in Kasugayama Forest，the oldest urban forest in the world．It was started more than a thousand years ago，and today it’s very popular with tourists．and artists．
Cities around the world are working to protect their urban forests．Some urban forests are parks， and some are iust streets with a lot of trees．But all urban forests have many good effects oil the environment．___________ (47)They also stop the noise from heavy traffic．They even make the weather better because they make the air 3—5 degrees cooler，and they stop strong winds．
Urban forests also have many good effects on people．They make the city more beautiful．In a crowded area，they give people a place to relax and spend time in nature．___________ (48)
In some countries，people are starting new urban forests．In England，there are now l．3 million trees in an urban forest called Thames Chase，east of London．It was started in l 990，and it has grown very fast．Walking and bicycle clubs use the forest，and there are programs for children and artists．___________ (49)
Some older cities don’t have space for fl big urban forest，but planting trees on the streets makes the city better．Scientists found that commuters(通勤人员)feel more relaxed when they can see trees． Trees are even good for business．___________ (50)In the future，urban forests will become even more important as our cities grow bigger．In the megacities(超大城市)of tomorrow，people will need more green space to live a comfortable life．Planting trees today will make our lives better in the future．
A. People spend more time at shopping centers that have trees.
B. In hot countries, urban forests are cool places for walking.and other healthy exercises.
C. But you are not in rural area.
D. Trees take pollution out of the air.
E. In 2033, it will have 5 million trees.
F. It has many kinds of birds in the country.
__________
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