1.вставь нужные слова в предложения.try my chance, out of luck, lose, miss a very good chance, a waste of time i never take part in any competition. i am always….that is why it’s not worth trying. any competition for me is…for me. last year i tried to take part in sport competition in our school. i lost it.b). i always take part in different part competitions. sometimes i win the competition and sometime i ….it. it’s not very important for me if i win or lose. the main thing is to …. , because if you don’t believe in your luck, you can….

Inever take part in any competition. i am always  out of luck  that is why it’s not worth trying. any competition for me is  a waste of time for me. last year i tried to take part in sport competition in our school. i lost it.b). i always take part in different part competitions. sometimes i win the competition and sometime i lose  it. it’s not very important for me if i win or lose. the main thing is to  try my chance , because if you don’t believe in your luck, you can  miss a very good chance

Air is the most important element for all living organisms, and yet, most people play a big role in contaminating this essential resource. air pollution can be just as dangerous as nuclear pollution or water pollution, but in the long term it will have a huge impact on the environment and the health of organisms living on the planet. asthma, cancer, and disability as a result of improper photosynthesis are just one of the causes of polluted air. to atmospheric pollutants with the most negative effect on the environment are: carbon monoxide, carbon dioxide, hydrocarbons, sulfur dioxide, nitrogen oxides, dust particles, radioactive isotopes and chlorofluorocarbons. the main sources that produce carbon monoxide are car exhausts, fossil fuel combustion, and oxidation of natural methane. carbon dioxide, caused by the consumption of only fossil fuels, leads to a possible greenhouse effect that leads to global warming. hydrocarbons are caused by the burning of oil and gasoline, and this affects the environment with large releases of negative carcinogens. a carcinogen is a chemical element that causes cancer. sulfur dioxide is certainly considered to be one of the main pollutants of the atmosphere, and it causes burning sensation in the eyes, lung damage, asthma, and acid rains. this is the result of the operation of coal-fired power plants. nitrogen oxides, which are obtained by exhausting cars, causes pneumonia and asphyxiation. the outcome of well-known dust particles is often underestimated. this is caused by work, industrial chimneys, car exhausts and volcanic eruptions, and this affects the environment by toxic effects and lung damage. radioactive isotopes that are caused by nuclear waste and nuclear accidents have a carcinogenic effect on the environment. the result of the chernobyl disaster, which was first discovered in the 1980s, is that it destroys the ozone layer. many of these large air pollutants in combination produce dangerous and well-known fumes and gases called smog. smog and dust domes are most often formed when a layer of cold air is trapped under a layer of even warmer air. a mixture of benzopyrene (causing cancer by a substance that is produced by evaporation of gasoline), hydrocarbon waste, combined with nitrogen dioxide, oxygen and sunlight produce a photochemical smog that can be reflected as a yellow cloud over every big city in the world. in addition to this optical effect, this causes an increase in ozone in the lower layers of the atmosphere and the state of health of a particular organism living in such an area. for example, it is believed that "moscow receives 10% less light than in previous centuries due to the protection of atmospheric pollution." in addition to this, it causes skin cancer in humans. and this all raises the acidity of the rain, which is mainly caused by the rise of sulfur dioxide and nitrogen oxides, which subsequently penetrates the clouds. in this polluted rain, a little acid is added by dissolving carbon dioxide, after which the contaminated rain becomes very acidic. the effect of acid rain on terrestrial and aquatic ecosystems can be very different. "in scandinavia, which receives a large share of air pollution from the uk, scientists noted that productive lakes are now completely devoid of fish." in addition to direct effect on water, acid rains carry metal ions, such as aluminum, which is very toxic and dangerous for the fish family. acid rain decreases the growth of trees and deprives plants of the ability of photosynthesis, which destroys them in the long run. it also reduces the activity of nitrogen-fixing bacteria. in the event of a nuclear accident or war, the main risks do lie only partially in the air and air pollution as a carrier of contaminated particles. the main risks are associated with the inhalation of pollutants, the deposition of radioactive isotopes on the soil with subsequent inclusion in food, and contamination of water sources. the results of all these polluting factors are enormous. smoke from car engines that contain lead, which causes brain damage in children, burning eyes, lung damage, patient mortality increases every year, and the destruction of whole forests includes only a few examples of the effects of air pollution on the environment. there are many ways to limit and reduce air pollution, and this is not the lack of technology, but the reluctance of people to change their attitude to nature and lifestyle.