________ recent developments we do not think your scheme is practical.

________ recent developments we do not think your scheme is practical.

A．In view of

B．In favor of

C．In case of

D．In memory of

__________recent developments we do not think your scheme is practical．

A.In view of

B.In case of

C.In memory of

D.In favor of

A.In view of

B.In case of

C.In memory of

D.In favor of

.______recent developments we do not think your scheme is practical.

A) In view of              B) In favor of

C)In case of               D)In memory of

During recent years we have heard much about "race": how this race does certain things and that race believes certain things and so on. Yet, the【51】phenomenon of race consists of few surface indications.

We judge race usually from the coloring of the skin: a white race, a brown race, a yellow race and a black race. But【52】you were to remove the skin you could not tell anything about the race to which the individual belonged. There is nothing in physical structure, the brain or the internal organs to【53】a difference.

There are four types of blood. All types are found in every race, and no type is distinct to any race. Human brains are the【54】No scientists could examine a brain and tell you the race to which the individual belonged. Brains will【55】in size, but this occurs within every race.【56】does size have anything to do with intelligence. The largest brain ever examined belonged to a person of weak【57】. On the other hand, some of our most distinguished people have had【58】brains.

Mental tests which are reasonably【59】show no differences in intelligence between races. High and low test results both can be recorded by different members of any race.【60】equal educational advantages, there will be no difference in average standings, either on account of race or geographical location.

(51)

A．complete

B．full

C．total

D．whole

Where Have All the Frogs Gone?

In the 1980s, scientists around the world began to notice some.thing strange: Frogs were disappearing. More recent research has shown that many kinds of amphibians (两栖动物)" are declining or have become extinct. They have been around for a long time-over 350 million years. Why are they dying out now?

Scientists are seriously concerned about this question. First of all, amphibians are an important source of scientific and medical knowledgE．By studying amphibians, scientists have learned about new substances that could be very useful for treating human diseases. Further research could lead to many more discoveries, but that will be impossible if the amphibians disappear.

The most serious aspect of amphibian loss, however, goes beyond the amphibians themselves. Scientists are beginning to think about what amphibian decline means for the planet as a wholE．If the earth is becoming unlivable for amphibians, is it also becoming unlivable for other kinds of animals and human beings as well?

Scientists now believe that amphibian decline is due to several environmental factors One of these factors is the destruction of habitat, the natural area where an animal lives. Amphibians are very sensitive to changes in their habitat. If they cannot find the right conditions, they will not lay their eggs. These days, as wild areas are covered with houses,roads, farms, or factories, many kinds of amphibians are no longer laying eggs. For example, the,arroyo toad (蟾蜍) of southern California will only lay its eggs on the sandy bottom of a slow-moving stream. There are very few streams left in southern California,and those streams are often muddy because of building projects. Not surprisingly, the arroyo toad is now in danger of extinction.

There are a number of other factors in amphibian declinE．Pollution is one of them. In many industrial areas, air pollution has poisoned the rain, which then falls on ponds and kills the frogs and toads that live therE．In farming areas, the heavy use of chemicals on crops has also killed off amphibians. Another factor is that air pollution has led to increased levels of ultraviolet (UV) light. This endangers amphibians, which seem to be especially sensitive to UV light. And finally, scientists have discovered a new disease that seems to be killing many species of amphibians in different parts of the world.

All these reasons for the disappearance of amphibians are also good reasons fot more general concern. The destruction of land, the pollution of the air and the water, the changes in our atmosphere, the spread of diseases - these factors affect human beings,too. Amphibians are especially sensitive to environmental changE．Perhaps they are like the canary(金丝雀)bird that coal miners once used to take down into the mines to detect poisonous gases. When the canary became ill or died, the miners knew that dangerousgases were near and their own lives were in danger.

第 37 题 Losing amphibians means losing

A．knowledge about fatal human diseases.

B．knowledge about air and water pollution.

C．a chance to discover new medicines.

D．an opportunity to detect poisonous gases.