Some children cannot wait to grow up. Because once you become an adult you are free to make your own decisions. More importantly, you can do all those things that you cannot do now because you are too young. So the question is “At what age do you really become an adult?” Well, people become adults at different ages in different places.
In Australia, the 18th birthday is a very important event for young Australians because it means they can do almost anything they want. They can vote(选举), learn to drive a car, get married, join the army and even buy their own houses. Even if they can do all these things, most Australians have to wait until their 21st birthday to really celebrate becoming an adult. This is the traditional adult age in Australia, the USA and the UK.
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In China, you can vote and learn to drive a car when you are 18, but if you want to get married, women have to wait until they are 20 and men until they are 22. Chinese people celebrate important birthdays every 10 years.
No matter what age you are, becoming an adult is really about learning how to be independent and responsible(负责任的). Once you are finally able to take care of yourselves and make your own decisions, then you can say that you are truly all grown - ups.
What is the main idea of the passage?

A.Why some children can’t wait to grow up.
B.People become adults at different ages in different places.
C.What people can do at different ages.
D.How to become an adult.

点拨：通读全文可知，文章主要讲述在不同的国家和地区，成为成年人的年龄不同。主旨句为文章第一段的末句“Well, people become adults at different ages in different places.”。故选B。

【解析】
通读全文可知，文章主要讲述在不同的国家和地区，成为成年人的年龄不同，文章第一段的末句“Well, people become adults at different ages in different places.”是主旨句，结合文中澳大利亚、中国等国家的具体例子，可确定答案为B。
【答案】
B
【知识点】
阅读理解主旨题、跨文化年龄差异
【点评】
本文通过列举不同国家的成年年龄规定，考查学生抓取文章主旨的能力，解题需找准主旨句并结合全文内容判断。
【难度系数】
0.7

In recent years, sandstorms haven’t been as common in northern China as before. The land with desertification(沙漠化)has been falling per year in China, and the area of sand land has been decreasing every year. This is thanks to China’s Three - North Shelter Forest Program(TNSFP，三北防护林工程)which started in the 1970s. Millions of trees have been planted in northern China to prevent sandstorms and protect the environment.
The underlined word “decreasing” means “”.

A.going up
B.putting down
C.going down
D.rising up

点拨：根据上文中的“sandstorms haven’t been as common in northern China as before”和“The land with desertification(沙漠化)has been falling per year in China”可知，中国的沙漠化状况有所好转。由此可推测，画线词所在句的第二个分句表示沙地面积每年都在减少，从而可推测出decreasing表示“减少”，与going down同义。故选C。

【解析】
根据上文“sandstorms haven’t been as common in northern China as before”以及“The land with desertification(沙漠化)has been falling per year in China”可知，中国沙漠化情况有所好转，由此可推测沙地面积每年都在减少，所以“decreasing”表示“减少”，与“going down”同义。故选C。
【答案】
C
【知识点】
词义猜测、语境推断
【点评】
本题考查词义猜测能力，需结合上下文语境信息推测单词含义，解题关键是抓住文中描述环境改善的相关语句来判断词义。
【难度系数】
0.7