题目内容：

（1）1.(get) rid of garbage problems, the city will load huge spaceships with waste materials 2. send them towards the sun, 3.(prevent) landfill and environmental problems.

All cars will be powered by electricity, solar energy or wind, and 4.will be possible to change the color of cars 5. the flick of a switch.

（2）Li Hua and Wang Hai are two students of Senior Three. 6.of them work hard but they have various learning methods.

Li Hua listens to her teachers7.(attentive) and asks her teacher  8.help as soon as possible if she has some problems. Because of this, she spends less time 9.(do) her homework, so it is10.(certainly) that she can keep energetic in the day. However, Wang Hai has quite a11. (difference) way of learning 12.(compare) to Li Hua. He likes to sit up late at night doing his homework, so he often feels sleepy in class. As a result, he misses lots of key points, 13.makes it difficult for him 14.(concentrate) on what he is doing.

In my opinion, Li Hua learns more effectively in class and has more free time to enjoy herself. So I prefer15.(she) learning method.