Greg Woodburn, a university student, spends a lot of time cleaning sports shoes. Some of them once belonged to him; some belonged to his friends. But soon the shoes will have new owners, poor children in the USA and 20 other countries, thanks to Greg's Share Our Soles(鞋底) (S.O.S) charity. 
    Greg was a high school running star in a small town in California. He had to stop running for months because his knee was injured. "I started thinking about all the things I got from running, the health, the friendships and the confidence."he says. And I realized there are children who don't even have shoes.
    Greg collected his own sports shoes and then called his friends and the town. His aim was to have 100 pairs by Christmas 2006. When the number climbed to more than 500 pairs. Greg know that he could collect sports shoes all year round.
    Now he has set up collection boxes in his town. So far, S.O.S has collected and donated more than 3,000 pairs of shoes. And Greg has cleaned almost all of them. “People think of it as duty work,”he says, "but I like doing it, because I feel happy when I'm doing it. It's not work I want to pass on to someone else.”
    In just three years, Greg has started three branches(分部) of S.O.S and there are more and more sports shoes.
    For many poor children who have received the shoes mean opportunity. Two young boys in southern California used to go to school on alternate days(隔日) because they both shared a pair of shoes. They were too big for one boy and too small for the other. Thanks to S.O.S, each brother received his own pair of shoes. The boys now go to school every day. When they graduate, they say they will help others, just as Greg helped them.

下列各组中的文学常识完全搭配正确的一项是 （      ）

—Would you like to come to dinner tomorrow evening？  —____.

阅读理解

    To prevent the deserts coming near, China has planted billions of trees—to replace destroyed forests and as barriers against the sand. This isn't a cure, though, say experts, as thirsty trees can make the problem worse by taking in groundwater.

    “Planting tress is one way, but it isn't that simple. It doesn't solve the basic issue of water resources,” says Wu Bo, a professor. “We need to calculate how much water the trees will absorb, or else it could have a negative effect.”

    Villagers in Zhengxin have taken on this challenge, with limited success. When the irrigation channels began to run dry, Lu Xianglin switched from wheat to cotton on his land. He also planted trees to protect his fields from sandstorms. He says he still gets good yields（产量） using flood irrigation and earns a good income for his family.

    Other farmers haven't stuck it out（坚持到底）: about one in three have left Zhengxin in the past 10 years after their wheat crops died. Young people who can find jobs in the towns rarely return.

    Last week, Mr Lu joined the other men in his village on a government-arranged trip to see the land that has been set aside for their relocation, nearly 40 miles to the south. The next day, he was back, shaking his head at the plan. The idea of uprooting his family troubles him, as does the idea of giving up the land that fed his forefathers. He prefers to stay and keep up the fight.

    “With enough water, this problem can be solved,” Lu says. “We can plant trees and grass, and they will grow bigger. That will stop the desert.”

    Experts say that farmers could switch to drip irrigation （滴灌）to lessen their water intake for growing crops. Elsewhere in the region, farmers have built brick greenhouses as part of a plan to grow vegetables using less water. Roadside signs urge farmers to “Save Water, Protect the Environment”.