[判断题]

Scientists know more about competing theories of uncertainty, so they are closer to solving a problem.

[单项选择]Scientists have advanced many theories about why human beings cry tears , none of （） has been proved.
A. whom
B. which
C. what
D. that

[填空题]The scientific theories about the origin of language include the bow-wow theory, the pooh- pooh theory and the "yo-he-ho" theory.（）

[填空题]Most theories about the evolution of Earth have the same general point of view.

[单项选择]There are many theories about the beginning of drama in ancient Greece. The one most widely accepted today is based on the assumption that drama evolved from ritual. The argument for this view goes as follows. In the beginning, human beings viewed the natural forces of the world, even the seasonal changes, as unpredictable, and they sought through various means, to control these unknown and feared powers. Those measures which appeared to bring the desired results were then retained and repeated until they hardened into fixed rituals. Eventually stories arose which explained or veiled the mysteries of the rites. As time passed some rituals were abandoned, but the stories, later called myths, persisted and provided mate rial for art and drama.
Those who believed that drama evolved out of ritual also argue that those rites contained the seed of theater because music, dance, masks, and costumes were almost always used. Furthermore, a suitable site had to be provided for performances,

[填空题]Our theories about human disease are the product of current fashion 1. ______.
than we would like to admit. But just as the moment influences the hemline
and the automobile fender, so too a type of intellectual currency 2. ______.
affect our understanding of how illness happens. Much of
the 20th century is spent in pursuit of external causes of 3. ______.
disease - cigarettes, fatty foods, tick bites. Rather like the hero in an old western,
medicine’s work was to track down the bad guys, round them up 4. ______.
and squish them before a real commotion. Antibiotics, vaccines,
heart pills - these were our weapons in the epic battle betw

[单项选择]One of the many theories about alcoholism is the learning and reinforcement theory, which explains alcoholism by considering alcohol drinking as a reflex response to some stimulus and as a way to reduce an inner drive state such as fear or anxiety. Characterizing life situations in terms of approach and avoidance, this theory holds that persons tend to be drawn to pleasant situations or repelled by unclean, sanity ones. In the latter case, alcohol drinking is said to reduce the tension or feelings of unpleasantness and to replace them with the feeling of pleasure generally observed in most persons after they have consumed one or more drinks.
Some experimental evidence tends to show that alcohol reduces fear in an approach-avoidance situation. Conger trained one group of rats to approach a food goal and trained another group to avoid electric shock. After an injection of alcohol the pull away from the shock was measurably weaker, while the pull toward food was unchanged.
The o
A. concludes that alcohol drinking may affect appetite.
B. confirms the findings of other academic researchers.
C. shows that alcohol minimizes fear.
D. disproves learning and reinforcement theory.