According to John May, the population expert from World Bank, the solution to the overpopulation in Africa is ______.

Service contract is a part of the deal.

Instead of an aspect of nature, sports belong to the field of ______.

The example of Rembrandt&39;s painting suggests that a distinction should be made between______.

Business major as he is, he has ____ (从未考虑过从事推销员的工作).

Our earth has been threatened by all kinds of pollutions.

Acid rain is a kind of air pollution which is hanging

over our heads and coming down from many different 【S1】__

ways such as rain and snow. It damages forests, lake and 【S2】__

rivers, buildings and even human health. Several

chemicals, including of sulfur dioxide, nitrogen 【S3】__

oxides and ozone, are involved in causing acid rain.

These chemicals either come directly from power

station chimneys and cars, and are formed from a 【S4】__

combination of pollutant gases. Sulfur dioxide is the

one chemical what is often associated with acid rain. 【S5】__

It is mainly emitted by large coal burning power

stations. It affect places thousands of miles away as 【S6】__

well as areas around the power stations. To prevent

more or worse environmental effects from acid rain, 【S7】__

we have short-term and long-term solutions. We should 【S8】__

just clean up our power station chimneys and car exhausts.

We should also change the way society thinks and reacts.

We need to conserve energy by decreasing efficiency. 【S9】__

We also need to change our way of transport, that is,

create a more efficient transport system which

depends less on private cars and more a good public 【S10】__

transport network. Everybody should work together

to save the world.

【S1】