下面的summary字数略多,请通过学习的修改方法,对该summary进行修改。 Read and revise the summary Every year, there are several tons of soil flowing into the Yellow River. The erosion it causes is threatening the land along the River. Shaanxi is one the provinces which are seriously affected by that. The issue has to be dealt with. In fact, only 5 yuan can play an important part in protecting the soil. If everyone spends 5 yuan on a tree, the soil will stay on the land and the farmers will have rich soil to grow crops. As a result, it will bring benefits to local economies. Take Jiuchengong Valley as an example. The tree planting programme started in 1997 has not only changed it into a green land, but also improved the lives of people there. So why don't we use 5 yuan to created a green future for human beings?