函数处的切线方程是( ) A. B. C. D. 答案:DThe word “conservation” has a thrifty
meaning. To conserve is to save and protect, to leave what we ourselves enjoy
in such a good condition that others may also share the enjoyment. Our
forefathers had no idea that human population would increase faster than the
supplies of raw materials: most of them, even until very recently, had the
foolish idea that the treasures were “limitless” and could “last forever”. Most
of the citizens of earlier generations knew little or nothing about the
complicated and delicate system that runs all through nature, and which means
that, as in a living body, an unhealthy condition of one part will sooner or later
be harmful to all the others.
Fifty years ago, nature study was not part
of school work; scientific forestry was a new idea; wood was still cheap
because it could be brought in any quantity from distant woodlands; soil
destruction and river floods were not national problems; nobody had yet studied
long-term climatic cycles in relation to proper land use; even the word
“conservation” had nothing of the meaning that it has for us today.
For the sake of ourselves and those who
will come after us, we must now set about correcting the mistakes of our
forefathers. Conservation should be made part of everybody's daily life. To
know about the water table (水位) in ground is just as important to us as a knowledge of the basic
math formulas(公式).
We need to know why all watersheds (上游集水区) need the protection of plant life and why the running current of
streams and rivers must be made to give their full benefit to the soil before
they finally escape to the sea. We need to be taught the duty of planting trees
as well as of cutting them. We need to know the importance of big, grown trees,
because living space for most of man's fellow creatures on this planet is
figured not only in square measure of surface but also in cubic(立方体的) volume above the earth. In a word, it should be our goal to restore as much of the original
beauty of nature as we can.
1.The author's attitude towards the use of
natural resources is_________.
A.positive
B.uninterested
C.optimistic
D.critical
2.According to the author, the greatest
mistake of our forefathers was that________.
A.they had no idea about scientific forestry
B.they had little or no sense of environmental protection
C.they were not aware of the importance of nature study
D.they had no idea of how to make good use of raw materials
3.To avoid repeating the mistakes of our
forefathers, the author suggests that ________.
A.we plant more trees
B.natural sciences be taught to everybody
C.environmental education be given to everybody
D.we return to nature
4.How can you understand the underlined
sentence in the last paragraph?
A.Our living space on the earth is getting smaller and smaller.
B.Our living space should be measured in cubic volume.
C.We need to take some measures to protect space.
D.We must preserve good living condition for both birds and animals.