These days young people give up when there's the (4)________ argument.

There are many sources of pollution in our modern world. At present, the most severe sources are acid rain, car exhaust fumes and oil spills. Factory chimneys give (1)______ smoke that contains sulfur dioxide and nitrogen oxide. These gases combine with the moisture in the atmosphere to (2)______ sulfuric acid and nitric acid. When it rains, these acids dissolve in the rain and turn it acidic. Acid rain is thought to be the worst pollution problem of all. It has (3)_____ aquatic life by turning many lake into lifeless bodies of water. In these areas, there is no limestone in the rocks to neutralize the acid rain naturally. One remedy is to pump limestone into the acidic lakes. (4)_______ , it is not possible to do this on a large enough scale to save all the lakes. Car exhaust fumes contain carbon monoxide and lead which are highly poisonous. In big cities, the exhaust fumes build (5)______ and pose a health hazard to human beings. Pollution of the sea by oil threatens marine life. Much of the oil comes from ships that clean their fuel tanks while at sea. Offshore oil wells also discharge vast amounts of oil into the sea. Pollution of the sea can also be caused by oil spills. An oil spill may occur as a result of accidents involving oil tankers.

As health and education are the State's (4)_____ , they affect the country's finances. So in developing countries health and illiteracy continue to be the problem. The unwieldy growth of population leads to the problem of housing and sanitation.

Another popular scene involves an automatic feeding machine brought to the assembly line (3)______ workers need not interrupt their labor to eat. The feeding machine malfunctions, hurling food at Chaplin who is strapped into his position on the assembly line and cannot escape.

Two–way (1)_____ depends on having a coding system that is understood by both sender and (2)_____ , and an agreed convention about signaling the beginning and end of the message.

For example, lowering the pitch of the voice may mean the end of a sentence, a sharp intake of breath may signal the desire to interrupt, catching the chairman’s eye may indicate the desire to speak in a formal setting like a debate, a clenched fist may indicate anger. When (5)_____ possible, more formal signals may be needed.

Secondly, there's too much testing and not enough learning. My fifteen–year–old daughter, for example, has just spent the last month or so (2)_____ for exams.

However, as the (2) snakes grow, they become more difficult to cafe and handle. To avoid dealing with the snakes, the owners irresponsibly
release them into the wild. 

Knowing such details about your best friend or loved one (3)_____ also tell you about the type of friend or partner he needs.

Noise effects can be (5)_____ by a number of techniques, for example, increasing the distance or blocking the path between the noise source and the recipient, reducing noise level at the source, and protecting recipients with earplugs or earmuffs

The Olympics are also an opportunity to invest in projects (5)_____ improve the city’s quality of life, such as new transportation systems