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图中的①、②分别是钠元素、氯元素在周期表中的信息,A、B、C、D是四种粒子结构示意图。

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    As most people know, in the last few years, sandstorms have swept across many cities and areas of North China, polluting the air and disturbing daily lives of human beings. People look dirty and suffer many kinds of illnesses, such as breath difficulty. The sandstorm is such a serious problem that it has not only weakened the industrial and agricultural development of our country but also caused a lot of trouble to the living conditions of the Chinese people.

    Therefore, effective measures should be taken as soon as possible to stop its happening. So how should we deal with the frightening sandstorms?

    Some experts offer practical advice as follows: For one thing, more money ought to be put into tree planting and forest protection in order to keep more water on the Earth. For another, government of all countries should make laws on environment protection. For example, banning the use of throw-away chopsticks and punishing illegal tree cutting. Scientists should also study and find ways to lower the grade of its destruction and to improve the environment. As for some schools, education about sandstorms should be spread properly and timely to make more and more people attach great importance to this problem.

    How people look forward to sunny days with soft wind touching their faces now and forever! The golden days can come back so long as we try our best to protect the natural environment from today on. And the fact is that what I expect is not just a dream. There are some sweet fruits from the early efforts.