Which set of level four is the karez?

The third set.

December 2021 College English Level 4 Translation Exam Questions and Sample Essays: Karez (Third Online Version).

Karez is a water conservancy system in arid areas of Xinjiang, consisting of underground channels connecting wells. This system collects a large amount of rainwater and snowmelt water that seeps into the ground in spring and summer, and leads it to the ground through the natural slope of the mountain, where it is used to irrigate farmland and meet people's daily water needs. Qanat reduces the evaporation of water on the ground and causes little damage to the surface, thus effectively protecting natural resources and the ecological environment. The karez embodies the wisdom of our people to live in harmony with nature and is a major contribution to human civilization.

Karez is a water conservancy system found in the dry region of Xinjiang, in which underground channels join wells to-gether. The system collects a large amount of rainwater and melted snow water that seep underground, and drains the water to the ground by the natural mountain slope for the irrigation of fields and the daily use. Karez reduces the evap-oration on the ground and does little harm to the surface, thus protecting natural resources and the ecological envi-ronment effectively. The system embodies the Chinese wisdom that people and nature co-exist in harmony, and is well recognized as a major contribution to the human civili-zation.