正确答案：They decrease water conservation.

8、Concerning the alternating fields method， which of the following are TRUE？

A.Crop seeds are sowed on the ridges in order to help them resist wind and preserve moisture.

B.Crop seeds are sowed in the furrows in order to help them resist wind and preserve moisture.

C.The furrows and ridges of the field are rotated every year.

D.This farming method increases land-use efficiency.

正确答案：Crop seeds are sowed in the furrows in order to help them resist wind and preserve moisture.The furrows and ridges of the field are rotated every year.This farming method increases land-use efficiency.

9、Terraces can be found in（）.

A.Hunan Province

B.Jangxi Province

C.Guizhou Province

D.Fujian Province

正确答案：Hunan Province；Jangxi Province；Guizhou Province；Fujian Province

10、Which of the following statements are right？

A.The sandy layer on top of sandy fields allows more rainfall to soak into the soil if it rains.

B.The sandy layer on top of sandy fields slows water evaporation down if it doesn’t rain.

C.The sandy layer on top of sandy fields absorbs the sun’s heat into the soil more slowly.

D.The sandy layer on top of sandy fields dissipates the soil heat into the atmosphere more

slowly.

正确答案：The sandy layer on top of sandy fields allows more rainfall to soak into the soil if it rains.The sandy layer on top of sandy fields slows water evaporation down if it doesn’t rain.The sandy layer on top of sandy fields absorbs the sun’s heat into the soil more slowly.The sandy layer on top of sandy fields dissipates the soil heat into the atmosphere more

slowly.

第四章单元测试

1、Dayu proposed the concept of Jiuzhou.。

A.正确

B.错误

正确答案：正确

2、Dayu was the first person to build water engineering projects in the worlD.。

A.正确

B.错误

正确答案：错误

3、The Grand Canal has been listed as World Heritage by UNESCO in 2014.。

A.正确

B.错误

正确答案：正确

4、Feishayan helps to prevent water running out of the water channel.。

A.正确

B.错误

正确答案：错误

5、When Li Bing built Yuzui Isle， he used Zhulong and Macha， a highly effective yet low-cost method， to prevent dirt and stones being washed away by fast running water.。

A.正确

B.错误

正确答案：正确

6、Which of the following statements is true about Dayu？