Read the following passage and mark the letter A, B,C or D on your answer sheet to indicate the correct word or phrase that best first each of the numbered blanks
Humans are destroying the earth’s tropical rain forests. About 80,000 square kilometers are being  destroyed  every  year. About a quarter of the (38)_____ comes from people cutting trees for fuel. Another quarter is to make grassland for their cattle. The (39)______ trees are cut down to sell the wood to start farms.
The population in cities all over the world is growing, and more and more wood is needed to build huge new buildings. For example, 5,000 trees from Sarawak rain forest in Malaysia were used to build just one tall building. (40)_______ people continue cutting down that many trees in Sarawak rain forest, all the trees could be gone in eight years.
The world needs more food, and it (41)______ like a good idea to clear the rain forests and use the land for agriculture. Many people think that the land under these huge, thick forests must be in rich nutrients, but it isn't. This is another surprising thing about rain forests. Most of the land in tropical rain forest is very (42)________.
(40)_______
A.Unless     
B.If      
C.While       
D.Although

Các câu hỏi liên quan

Read the following pasage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions
Any list of the greatest thinkers in history contains the name of the brilliant physicist Albert Einstein. His theories of relativity led to entirely new ways of thinking about time, space, matter, energy, and gravity. Einstein's work led to such scientific advances as the control of atomic energy, even television as a practical application of Einstein's work.
In 1902 Einstein became an examiner in the Swiss patent office at Bern. In 1905, at age 26, he published the first of five major research papers. The first one provided a theory explaining Brownian movement, the zig-zag motion of microscopic particles in suspension. The second paper laid the foundation for the photon, or quantum, theory of light. In it he proposed that light is composed of separate packets of energy, called quanta or photons, that have some of the properties of particles and some of the properties of waves. A third paper contained the "special theory of relativity" which showed that time and motion are relative to the observer, if the speed of light is constant and the natural laws are the same everywhere in the universe. The fourth paper was a mathematical addition to the special theory of relativity. Here Einstein presented his famous formula, E = m(cc), known as the energy mass equivalence. In 1916, Einstein published his general theory of relativity. In it he proposed that gravity is not a force, but a curve in the space-time continuum, created by the presence of mass. Einstein spoke out frequently against nationalism, the exalting of one nation above all others. He opposed war and violence and supported Zionism, the movement to establish a Jewish homeland in Palestine. When the Nazis came to power in 1933, they denounced his ideas. He then moved to the United States. In 1939 Einstein learned that two German chemists had split the uranium atom. Einstein wrote to President Franklin D. Roosevelt warning him that this scientific knowledge could lead to Germany developing an atomic bomb. He suggested the United States begin its own atomic bomb research.
The word “exalting”  in the passage is closest in meaning to       
A.criticism        
B.elimination      
C.support      
D.elevation