The word "conservation" has a thrifty (节俭) meaning.To conserve is to save and protect, to leave what we ourselves enjoy in such good condition so 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 this foolish idea that the treasures were "limitless" and "inexhaustible".  Most of the citizens or 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 the school work; scientific forestry (林地) was a new idea: timber (木材) 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 longterm 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 repairing the mistakes of our forefathers.Conservation should, therefore, be made a part of everyone's daily life.To know about the water table (地下水位) in the ground is just as important to us as a knowledge of the basic mathematic formulas.We need to know why all watersheds need the protection of plant life and why the running current of streams and river must be made to yield 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 themWe need to know the importance of big, mature trees, because   iving_space_for_most   _of_man's_fellow _creatures _on_this    _planet      _is_figured_not_only_in_square_measure_of_surface_   but_also_in_cubic_volume_above_the_earth.In brief, 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 present situation in the use of natural resources is ________.

A.  positive

B.  neutral

C.  critical

D.  suspicious

2.  According to the author, the greatest mistake of our forefathers was that ________.

A.  they had little or no sense of environmental protection

B.  they had no idea about scientific forestry

C.  they did not know the importance of nature study

D.  they had no idea of how to make good use of raw materials

3.  With a view to correcting the mistakes of our forefathers, the author suggests that ________.

A.  we plant more trees and make full use of the woodlands

B.  we be taught environmental science, as well as the science of plants

C.  we return to nature and not use any natural resources at all

D.  environmental education be directed toward everyone

4.  What does the author imply by saying "living space...above the earth" in the underlined sentence in

Paragraph 3?

A.  Our living space on the earth is getting smaller and smaller in volume.

B.  We must create better living conditions for both birds and animals.

C.  We need to take some measures to protect space in volume.

D.  Our living space should be measured in cubic volume.

5.  What's the best title for the passage?

A.  Our Forefathers' Big Mistake

B.  Improve the Living Conditions

C.  Protection of Our Resources

D.  Lead a Simple Life