It's March 12th. Lili and Linlin are digging on a hill not far from their school. In China, people across the country plant trees1on this day.
The idea of planting trees was first put forward in 1911 by Sun Zhongshan, the great2in China's history. He said more trees were needed as a3against flood and drought. In 1915, April 5th was named as Tree Planting Day. Then, in 1979, the day4to March 12th, to5the date on which Sun Zhongshan died.
"Everyone has heard of the Great Wall of China," says Lili. "But have you heard of the Green Wall of China? That's the biggest tree planting6of all." The Gobi Desert in the north of China was7every year. So in 1978, a tree planting project was started to8Gobi spreading. The government and local farmers have been planting millions of trees to build a great green "wall" along the edge of the desert.
"Tree planting has become a tradition in China now," says Linlin. "Many people do it on March 12th. Many people also plant a tree on a9day. My parents planted a tree when I started school. And my cousin planted10on his wedding day. We do it for the environment and for ourselves."
