In Hebei Province lies a vast forest called Saihanba. This green Great Wall,     1     at its peak during the Qing Dynasty covered thousands of hectares, had by the 1950s     2    （virtual）disappeared. This allowed sand to blow into Beijing from the northern deserts.

Saihanba is a combination of Chinese and Mongolian,     3    （mean）“beautiful highlands". Until the Qing Dynasty, it was a royal hunting land because of its cool summer weather and beautiful surroundings. However, most of the area had turned into a desert by the end of the Qing Dynasty.

In fact 56 years ago there was only one tree left. But without that tree, there     4    （be）no miracle of Saihanba today. In the early 1960s, over 350 foresters     5    （send）to this area to fight the desert. They were required     6    （rebuild）the forest in Saihanba. Few people, including the foresters themselves, believed they would succeed.

Their doubt disappeared, however, when they found the 200-year-old tree, swaying alone in     7     wind. If one tree could survive here,     8     could millions of trees, they thought.

After decades of hard work, three generations of the foresters have restored almost 80% of the original Saihanba forest. Recently, they were awarded the     9    （high）environmental honor from the United Nations for their great     10    （contribute）to creating a greener world.