更多"preserve（）"的相关试题:
[单项选择]David: Since attempting to preserve every species that is currently endangered is prohibitively expensive, the endangered species whose value to humanity is the greatest should be accorded the highest priority for preservation.
Karen: Such a policy would be unsound because it is impossible to predict the future value of a species, nor is it always possible to assess the present value of species whose contributions to humanity, though significant, are indirect.
Which of the following is the main point of Karen’s reply to David
A. Although it would be desirable to preserve all endangered species, doing so is not economically feasible.
B. Even if the value to humanity of a given species is known, that value should not be a factor in any decision on whether to expend effort to preserve that species.
C. Species whose contributions to humanity are direct should have a higher priority for preservation efforts than species whose contributions to humanity are only indirect.
D. Since the methods for deciding which species have the most value to humanity are imperfect, informed decisions cannot be made on the basis of the assessment of such value.
E. (E) The preservation of endangered species whose value to humanity can be reliably predicted is more important than the preservation of species whose value for humanity is unpredictable.
[填空题]To preserve tropical rainforests, social, political and economic factors all need to be______.
[填空题]
- A．make new materials
- B．preserve wetland and animals
- C．have clean air
- D．have clean water
- E．collect cigarette butts
- F．collect disposed oil
Joying placed the buckets at all public-access areas to ______.
[单项选择]A wildlife preserve is being planned for 3,000 rhinoceroses. The preserve is to contain a total of 10,000 acres of watering area, plus 100 acres of grazing area for each rhinoceros. If the number of rhinoceroses is expected to increase by 10 percent, how many thousand acres should the preserve have in order to provide for the increased population ？（）
A. 340
B. 330
C. 320
D. 310
E. 300
[单项选择]
To preserve food, the growth of bacteria (细菌) must be controlled. Water, warmth, and food are all needed for bacteria to become strong and healthy. Some kinds of bacteria need air, but other kinds grow only when air is absent. Extremes of temperature, either hot or cold, can kill bacteria.
Before electric ice boxes were invented, freezing and cooling were limited by the cold climate. In warmer regions, food was cooled by putting it in the shade, in cold water from the well, or in pits in the ground.
Cooking will usually kill bacteria if the temperature is high enough and long enough. Certain methods of cooking remove water, and this aids in preserving food. Drying is the oldest and most common method of preserving food. Food can be dried by the sun, by heat or by combination of the two.
Salt was used by many hunting people. When people began to cat vegetables, salt be came a needed part of their life. Salt helps to preserve food because it slows or stops b
A. cooking always kills the bacteria in food
B. cooking can make the food become dry
C. the light in cooking can kill bacteria
D. under the right conditions, cooking will kill bacteria
[填空题]The sea(preserve) ________ much of the heat it absorbs in the summer.
