121 EX Many parts of the world are losing important natural resources, such as forests, animals, or clean water. Choose one resource that is disappearing and explain why it needs to be saved . Use specific reasons and examples to support your opinion.
  
Many natural resources are disappointed of being wasted on our planet every day. One of the most important resources we are abusing is our trees. Each year , hundreds of thousands of acres of trees disappear in countries all around the world . In some countries , these trees are used for fuel. In other countries , trees are destroyed to build housing developments and shopping centers. Saving trees has become a major cultural and economical issue in many of the world.

Trees are essential to our survival . They are a major part of the process of photosynthesis . Photosynthesis is the process in which green plants use carbon dioxide to produce oxygen ,and oxygen is something all of us need . The fewer trees there are ,the more this affects our ability to breathe.

Trees are also important in the development of many medicines. The mainstream medical establishment did not recognize this for many years. However , those who use natural medicines have always known how important trees are. Now scientists are agreeing with them. Many drugs come from the leaves of certain trees, along with other herds and plants.

In rural areas, farmers have always known how important trees are to soil conservation. This is why you’ll usually see trees lining a field . Tree rots help keep the soil in place, and are also a factor in water distribution deep beneath the ground .

Finally ,we should save trees from disappearing because they provide so much pleasure. ‘I think that I shall never see a poem as lovely as a tree,’ wrote a poet . That is the truth . A tall , stately tree is beautiful to look at, and pleasing to the soul . It is also a great place to find shade on a hot summer’s day. For practical and emotional reasons, we need to preserve our planet’s trees.   

122 AD Do you agree or disagree with the following statement ?A zoo has no useful purpose. Use specific reasons and examples to explain your answer.
 
Zoos are often controversial because many people believe they are necessary or even harmful .If properly managed, I feel that zoos have a lot of value. In fact, I believe zoos are useful in two main ways: educating the general public and advancing scientific research.
    
Zoos can be wonderfully educational places. They provide a safe, controlled environment to learn about a specific species. Children can feel safe exploring the world of the chimpanzee there, and adults can learn about and see types of birds they’ve never seen before . Unlike in the wild , there’s no worry of being physically harmed by an animal.
    
Zoos are also important for the research opportunities they provide. Research is safer and easier to conduct than in the wild. Scientists can feel secure in the confined area of the Zoo. For example, while conducting a medical experiment in an open field ,scientists have to worry about both the animal they have to worked with, and also other animals nearby .In zoos, however ,they need only worry about the research subject.
    
In the wilderness, animals are also much harder to track and monitor. Zoos make research less time-consuming and expensive. Long term follows-ups are easier too, since even with monitors, wild animals often are killed and disappear. In zoos, researchers can observe an animal’s entire life span.
     
Overall , I feel that properly managed zoos provide excellent opportunities for education and research, and are therefore very useful.

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