biologically based instincts in determining how we will act. A behaviorist，B.F. Skinner，sees humans as beings whose behavior is almost completely shaped by their surroundings. The behaviorists maintain that，like machines，humans respond to environmental stimuli as the basis of their behavior.

　　Let us examine the different explanations about one human characteristic，intelligence，offered by the two theories. Supporters of the “nature” theory insist that we are born with a certain capacity for learning that is biologically determined. Needless to say，they don’t believe that factors in the environment have much influence on what is basically a predetermined characteristic. On the other hand，behaviorists argue that our intelligence levels are the product of our experiences. (64)Behaviorists suggest that the child who is raised in an environment where there are many stimuli which develop his or her capacity for appropriate responses will experience greater intellectual development.

　　The social and political implications of these two theories are profound. In the United States，blacks often score below whites on standardized intelligence tests. This leads some “nature” proponents to conclude that blacks are biologically inferior to whites. (65)Behaviorists，in contrast，say that differences in scores are due to the fact that blacks are often deprived of many of the educational and other environmental advantages that whites enjoy.

　　Most people think neither of these theories can yet fully explain human behavior.

 

1991年英译汉试题

　　The fact is that the energy crisis，which has suddenly been officially announced，has been with us for a long time now，and will be with us for an even longer time. Whether Arab oil flows freely or not，it is clear to everyone that world industry cannot be allowed to depend on so fragile a base. (71)The supply of oil can be shut off unexpectedly at any time，and in any case，the oil wells will all run dry in thirty years or so at the present rate of use.

　　(72)New sources of energy must be found，and this will take time，but it is not likely to result in any situation that will ever restore that sense of cheap and plentiful energy we have had in the times past. For an indefinite period from here on，mankind is going to advance cautiously，and consider itself lucky that it can advance at all.

　　To make the situation worse，there is as yet no sign that any slowing of the world’s population is in sight. Although the birthrate has dropped in some nations，including the United States，the population of the world seems sure to pass six billion and perhaps even seven billion as the twenty-first century opens.

　　(73)The food supply will not increase nearly enough to match this，which means that we are heading into a crisis in the matter of producing and marketing food.

Taking all this into account，what might we reasonably estimate supermarkets to be like in the year2001?

To begin with，