风沙止步的地方
Long ago, people in northern China had a big problem. The wind blew the sand everywhere. The sand covered their farms and houses.
So China started a big project in 1978. It is called the “Three-North Shelterbelt (防护林) Program”. Every year, many people plant trees. They water the young trees and take care of them.
Little by little, the green land comes back. Now, in 2026, Inner Mongolia has finished nearly 98% of its tree-planting work. The trees stop the wind and hold the sand. Birds and animals come back home.
A worker says, “The desert is becoming a green home. If we work hard, the desert will turn green.”
1.1. What was the big problem long ago?
A Sand got everywhere.
B There was too much rain.
C The rivers dried up.
D Their houses fell down.
解析：选A。A 细节理解题。根据第一段“The wind blew the sand everywhere. The sand covered their farms and houses.”可知，很久以前的问题是沙子到处都是；B“雨水太多”、C“河流干涸”文中没有提到，D“房子倒塌”文中也没说。故选A。
2.2. When did China start the big project?
A 48 years ago.
B 26 years ago.
C 22 years ago.
D 28 years ago.
解析：选A。A 数字计算题。根据第二段“So China started a big project in 1978.”“Now in 2026”可知，该项目是1978年开始的，现在是2026年，即2026-1978=48年前开始的。故选A。
3.3. What do people do for the young trees every year?
A They cut the trees down.
B They look after them.
C They sell the trees.
D They move them away.
解析：选B。B 细节理解题。根据第二段“They water the young trees and take care of them.”可知，人们给小树浇水、照顾它们，B项look after正是take care of的同义表达；A“砍树”与种树的目的相反，C“卖树”和 D“把树移走”文中都没有提到。故选B。
4.4. What is the main idea of the passage?
A Birds and animals came back home.
B People water young trees every year.
C Wind is bad for farms and houses.
D Trees are turning the desert green.
解析：选D。D 主旨大意题。全文讲人们种树治沙，末段工人说“The desert is becoming a green home... the desert will turn green.”可知文章主要讲树让沙漠变绿，D项概括了全文；A只说鸟兽回家、B只说浇水、C只说风的坏处，都只是文中的一小部分，以偏概全。故选D。