الوسم: الانجليزية

POLLUTION

Pollution is contamination by a chemical or other agent that renders part of the environment unfit for intended or desired use. It deserves emphasis that the environment also refers to the place where you live. Natural processes have released toxic chemicals into the environment throughout the history of the earth. Currently, the pollution generated by human activities presents the most serious problem.
There are basically 3 types of Pollution. They are:

1) Air Pollution
2) Water pollution
3) Land Pollution

Some of the major Causes of the Pollution are as follows:
i) Deforestation – For the establishment of factories, industries and due to urbanization in various parts of the world, trees are cut on a large scale without any adequate efforts to plant new trees. This leads to deforestation, which has caused a rise in the pollution levels and distortion of natural order.
ii) Polluted rivers – The wastewater and liquids from plants and factories are linked with nearby river water, which are polluted when they release disposal from these units. People in Developing/Undeveloped countries also pollute rivers by using the water in these rivers for washing clothes, utensils, bathing and other activities.
Oil spilled from ships pollute oceans around the world.
iii) Sound pollution – The machines used in factories make noise throughout the day, and this disturbs the peaceful atmosphere in the vicinity, as machines used without proper covering lead to sound pollution. This puts heavy mental strain on the people staying in the nearby areas.
iv) Air Pollution – Each year industrially developed countries generate billions of tons of pollutants. Many pollutants come from directly identifiable sources; sulphur dioxide, for example, comes from electric power plants burning coal or oil. Others are formed through the action of sunlight on previously emitted reactive materials (called precursors). For example, ozone, a dangerous pollutant in smog, is produced by the interaction of hydrocarbons and nitrogen oxides under the influence of sunlight. Ozone has also caused serious crop damage. The increasing number of vehicles have also lead to an increase in Air Pollution, due to the harmful gases like Carbon Monoxide emitted from these vehicles. Gases generated in the Chemical plants also cause air pollution. People suffer because of smoke and bad smell from the industrial units particularly from chemical plants.
v) Soil pollution – Dumping of wastes in many areas is a major cause of Soil Pollution. Also, when soil in and near production areas becomes dirty due to disposal of waste material, such land cannot be used for agricultural operations.
Pollution is also caused by iron and steel mills; zinc, lead, and copper smelters; municipal incinerators; oil refineries; cement plants; and nitric and sulphuric acid plants.

Effects Of Pollution Crisis:

Of the suite of pollutants that taint urban air, fine suspended particulate matter, sulphur dioxide (SO2), and ozone pose the most widespread and acute risks; however, airborne lead pollution is a critical concern in many cities as well. Recent studies on the effects of chronic exposure to air pollution have singled out particulate matter as the pollutant most responsible for the life-shortening effect of unhealthy air, although other pollutants may also play an important role. These pollutants cause respiratory and other health disorders.
Besides increasing blood pressure and stress levels, noise pollution can also have deleterious effects on hearing. There are two categories of hearing loss resulting from noise exposure. Acoustic trauma is hearing loss resulting from a single exposure to a very loud sound such as an explosion. Noise induced hearing loss is hearing loss arising from repeated exposure to moderate noise. The latter is the more common form of hearing loss due to noise pollution.
Water pollution infects the water and renders it unfit for drinking and other purposes. It is also a major cause of most of the water-borne diseases.
Awareness among masses, regarding the adverse effects of pollution around the world, can also help in reducing the intensity of pollution. This awareness can be created through various media like newspapers, television, radio, flyers, seminars, etc.

Measures Of Controlling Pollution
Various countries have set standards in legislation in the form of concentration levels that are believed to be low enough to protect public health. Source emission standards are also specified to limit the discharge of pollutants into the air, so that air-quality standards will be achieved. However, the nature of the problem requires the implementation of international environmental treaties, and to this end 49 countries agreed in March 1985 on a United Nations convention to protect the ozone layer. This “Montreal Protocol”, which was renegotiated in 1990, called for the phaseout of certain chlorocarbons and fluorocarbons by the end of the century and provides aid to developing countries in making this transition. In addition, several international protocols have been aimed specifically at reducing the incidence of acid rain. Awareness among masses, regarding the adverse effects of pollution around the world, can also help in reducing the intensity of pollution. This awareness can be created through various media like newspapers, television, radio, flyers, seminars, etc.
Conclusion
It is high time that we take this issue, of ‘Problems of Pollution’ seriously, or it could have adverse effects on our future generations

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السلام عليكم ورحمة الله وبركاته

Revision

Grade 8

Read the following passage, and then answer the questions below:

Norwalk virus is called the “winter virus” because it is common in winter. You can get it from shellfish. But the virus can also pass from a person to fresh vegetables. A cook with dirty hands can cause an outbreak. In an outbreak, hundreds or even thousands of people get ill at the same time. Outbreaks usually occur in hospitals, hotels or schools.
The virus is named after the town of Norwalk, in the northern USA. In 1968, more half the students and teachers at the primary school became ill. Scientists found the cause after four years. Now many different viruses in food are called Norwalk, Norwalk-like or Noroviruses.
If you cook shellfish properly, you will kill the virus. If you wash your hands before cooking, you will not pass the virus on. People usually become ill within 48 hours. The symptoms last for two or three days. The illness is not fatal People recover with no long term problems.

2- Norwalk virus is common in —————
a) Winter b- Summer c- Spring d- Autumn
3- Norwalk usually appears in————————– food
a) shellfish b) – frozen c)- fats d)- carbohydrates
4- If you cook shellfish properly, you will the———————- virus.
a) pass b) kill c) cure d) find
B- What do the underlined words in the passage mean?
1 –The word (dirty) line 2 means———————
a- clean b- not clean c- pure d- good
2 -The word (occur) line 4 means———————-
a- happen b- recover c- finish d- start
3 – How long do the symptoms of the illness last?
a-one day b- two or three days c- five days d- four days
4 -Where was first the virus discovered?
a-USA b- Canada c-UK d- UAE
Read the following passage then answer the questions below:
Faisal was born in 1905. He was the third son of Abdulaziz Bin Saud. His father was called lbn Saud by most people. He was the first king of Saudi Arabia.
Faisal’s mother, Tarfà died when he was young. He lived in the house of his mother’s father; he taught Faisal the Holy Qumran
In 1981, at the age of 13, Faisal became a soldier. Five years later, he was commander of the army in Asir province. In 1926 he became governor of Hijaz. This area has the city of Makkah. In 1932 he became minister of Foreign Affairs and in 1958 he was prime minister. Faisal became king on November 2’ , 1964 Faisal introduced many changes to the country, including schools for girls.
Faisal had 44 sons. In 1975 Faisal was killed at the age of 70

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