سؤال قراءة ستيب محلول — المفردات في السياق (تدريب 4478)

(1)Air is the ocean we breathe. It supplies us with oxygen which is essential for our bodies. Air is made up of a mixture of nitrogen, Oxygen, water vapor and inert gases. Human activities release substances into the air and some of these can cause problems for humans, Plants and animals. These Problems are usually referred to as air pollution. (2)There are several problems that result from air pollution. The main ones we usually hear about are smog, acid rain, the greenhouse effect and “holes” in the ozone layer. Each of these problems has serious implications for our health and well-being as well as for the environment as a whole. (3)The release of particles into the air from burning fuel for energy is often discussed as a huge problem. Diesel smoke is a good example of the particulate matter that results in this pollution. The particles are very small pieces of matter measuring about 2.5 microns or 0.0001 centimeter. This type of pollution is sometimes referred to as “Black Carbon” pollution. The exhaust from burning fuels in automobiles, homes, and industries is a major source of pollution in the air Authorities also believe that the burning of the wood and charcoal in fireplaces and barbeques release significant quantities of soot into the air. (4)Another type of pollution is the release of noxious gases, such as sulfur dioxide, carbon monoxide, nitrogen oxides, as well as chemical vapors. These take part in chemical reactions once they are in the atmosphere, resulting in smog and acid rain. (5)We must also consider air pollution inside our homes, offices, and schools. Some pollutants are created by indoor activities such as smoking and cooking. Most people spend about 80-90% of their time inside buildings. That means our exposure to harmful indoor pollutants can be serious. It is therefore important to consider both indoor and outdoor air pollutions.