[填空题]Smog is caused by chemical reactions between pollutants derived from different sources, primarily automobile exhaust and industrial emissions.

[填空题]Smog is caused by chemical reactions between pollutants derived from different sources, primarily automobile exhaust and industrial emissions.

[填空题]Chemical reactions in our brains change with what we think.

[简答题]In order to control and reduce environmental pollution caused by discarded waste electronic information products, save resources and promote sustainable development of the electronic information industry, according to the provision of the Administration on the Control of Pollution Caused by Electronic Information Products, the electronic information products sold in the market within the territory of China shall satisfy with the following requirements: the environmental protection materials，technologies and processes shall be introduced according to the national standards or sectoral standards；the safe-use life，names and contents of toxic and harmful substances contained therein and recovery marks shall be clearly indicated Off the products． non-toxic，harmless，readily degradable and recyclable materials shall be used as the packaging materials，and the materials ingredients of the packaging shall be clearly marked．

[简答题]This is an educational programme about Light Pollution. It has been arranged through the Ministry of Education and Religion with support and finance from the local government. The two-year programme will run from 2003 to 2005. The programme’s targets (目的) are to：1) Familiarize students with the problems of Light Pollution and study the problems through Astronomy (天文学), Physics and Computer Science; 2) Consider the cultural and social impacts of Light Pollution.

[填空题]Smog is fateful.

[单项选择]It is up to the Government to tackle the air pollution problem and （） measures in line with the council’s suggestions.
A. set about
B. work out
C. fill up
D. bring over

[单项选择]It is up to the government to tackle the air pollution problem and ______ measures in line with the council’s suggestions.
A. set about B. work out C. fill up D. bring over

[填空题]The (poison) ______ gases from the cars have polluted the air.

[填空题]Photochemical smog exists mainly in big cities.

[填空题]______(使用核能的一个优点) is that it won’t cause air pollution.

[填空题]Smog has become the most serious type of pollution.

[填空题]Photochemical smog is formed on rainy days when chemicals are combined with smoke.

[填空题]Smog does great harm to the respiratory system.