Built over 2, 200 years ago, Dujiangyan, is the world's oldest man-made water system, lies in Sichuan Province in Southwest China.This amazing engineering (achieve) is seen as a wonder in the development of Chinese science.

In ancient times, the region in which Dujiangyan now stands(suffer) from regular floods (cause) by overflow from the Minjiang River.(help) the victims of the flooding, Li Bing, the region governor, together with his son, decided to find a solution.Li designed a series of channels built at different levels along Mount Yulei that would take away the floodwater while leaving the river flowing naturally. (good) than ever, the extra water could be directed to the dry Chengdu Plain, making suitable for farming.

Once the system was finished, no more floods occurred and the people were able to live (peace). Today, Dujiangyan  (admire) by scientists from around the world because of one feature.Unlike modern dams where the water is blocked with a huge wall, Dujiangyan still lets water flow through the Minjiang River naturally, enabling ecosystem and fish populations to exist harmony.

锻炼不仅有助于健康，而且还能使你头脑清醒。