Icebergs – A Potential Source of Water 


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Icebergs – A Potential Source of Water



The supply of fresh water has not been a major problem for most countries in the world because a rainy season is part of their yearly climatic conditions. However, in countries where the rainfall is very sparse scientists must constantly seek ways to increase supplies of this precious element. Government planners in South America and the Middle East have been trying to devise ways of increasing their nations’ supplies of fresh water. The first method being considered is the use desalinization plants, which would remove salt from sea water. Another method being considered is the towing of icebergs. According to this method, large icebergs from Antarctica would be wrapped in cloth or plastic, tied to powerful tugboats by strong ropes, and towed to the countries needing fresh water. While this plan may have some potential, there are certain practical problems that must be solved.

The first problem ____________________________________________________is the expense. According to estimates, it would coast between $50 and $100 million to tow a single 100-million-ton iceberg from Antarctica to, for example, the coast of Saudi Arabia.

_________________________________________________________is the possibility that the iceberg would melt en route. No one knows if an iceberg could be effectively insulated during such a long journey. At the very least, there is the possibility that it would break up into smaller pieces, which would create still other problems.

________________________________________________________ there is the danger that a huge block of ice floating off an arid coast could have unexpected environmental effects. The ice could drastically change the weather along the coast, and it would probably affect the fish population.

_____________________________________________________ the cost of providing fresh water from icebergs would be less that the cost of providing water by desalinization, according to most estimates. It would cost between 50 cents and 60 cents per cubic meter to get water from an iceberg, as opposed to the 80 cents per cubic meter it costs to get the same amount by desalinization.

In conclusion, before icebergs can become a source of fresh water in the future, problems involving cost, overall practically, and most importantly, environmental impact must be solved.

 

 

Task 5 Add transition words, phrases, or clauses to the topic sentences of the paragraphs in this essay. Rewrite the topic sentences if necessary.

 

Medicine and Ethics

Recent advances in the fields of medicine and biotechnology have brought about situations that could scarcely be imagined only a generation ago. Battery-operated plastic hearts can be implanted into people. People can be kept alive indefinitely by machines. Exact duplicates of animals can be made. While such scientific achievements may ultimately benefit humankind, they have also created complex legal and ethical issues.

__________________________________________ involves doctors’ ability to intervene in human reproduction. A well-known example is the case of Baby M. A man paid a woman to bear a child for him and his wife, who could not have children. They signed a contract, but after the baby was born, the woman wanted to keep the baby. Then father said the baby was his, but the woman said it was hers. It took the courts many months to decide who was right.

_______________________________________________________________, another ethical dilemma has arisen because doctors are now able to keep people who are in comas alive for years by attaching their bodies to machines. This gives great power and great responsibility to the people who control machines. How does a person decide whether another person whose heart cannot beat on its own and whose lungs are pumped by a machine is still alive or not? As a result of this power, society has had to develop a new definition of death.

__________________________________________________________________ is the ability to transplant organs from one person into another. Doctors are now able to transplant hearts, lungs, livers, and kidneys from one human to another. Should doctors also be allowed to transplant organs from animals to humans? Such an operation was actually performed in 1987, when doctors transplanted a baboon’s heart into a dying human baby. The ethics of this experiment is still being debated.

________________________________________________, the ability of biotechnologists to produce new forms of life in their laboratories is another area with profound ethical consequences. Isn’t a scientist who creates, for example, a new bacterium “playing God”? Furthermore, is it even safe to introduce new life forms into the earth’s atmosphere? Is there a risk that such life forms could get out of control? Some people fear so.

_________________________________________________, scientists are now able to duplicate living organisms, cell by cell, through a process called cloning. Recently, the world was stunned by the successful cloning of an adult sheep. How long will it be before biotechnologists can clone people? Should they be allowed to? Who should control this?

________________________________________________ revolutions-political or technological-cause upheaval and force change. Our new ability to create and prolong life is raising questions and forcing changes in our very concept of life, an issue involving not only legal but also profound moral considerations.

 

The Writing Process The process of writing an essay is exactly the same as writing a single-paragraph composition. The following model shows how one student worked through the process of writing and revising drafts of his essay on modern technology. He has already developed the essay outline you can see on page 19. Notice that he doesn’t begin with the introductory paragraph. He begins with the body paragraphs. Many writers find it easier to get started if they begin with the body.

The First Rough Draft

 

The Writer’s Changes to the First Draft

 

 

 

 

 

 

 

 

 

PART 2

Speaking About Research

Word combinations and constructions useful while writing scientific papers, discussing and defending dissertations, preparing lectures, or talking on scientific subjects.



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