Questions 26-30 are based on the following passage.
The work 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 then the supplies of raw materials; most of them, even until very recently, had the foolish idea that the treasures were "limitless" and "inexhaustible". 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, and 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; scientific forestry was a new idea; timber 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 wil 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 in the ground is just as important to us as a knowledge of the basic arithmetic formulas. We need to know why all watersheds need the life and why the running current of streams and rivers must be made to yield their full benefit to the soil before they finally escape to the sea. We need to know the importance of big, mature 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 volume above the earth. In brief, it should be our goal to restore as much of the original as we can.
26. The author's attitude towards the current situation in the exploitation of natural resources is _____. A. positive B. suspicious C. neutral D. critical
27. 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 significance of nature study D. they had no idea of how to make good use of raw materials
28. It can be inferred from the third paragraph that earlier generations didn't realize _____. A. the interdependence of water, soil, and living things B. the importance of the proper use of land C. the harmfulness of soil destruction and river floods. D. the value of the
29. To avoid the mistakes of our forefathers, the author suggests that _____. A. we plant more trees B. natural sciences be taught to everyone C. environmental education be directed toward everyone D. we return to nature
30. What does the author imply by saying "living space …is figured…also in cubic volume above the earth" (Para. 3. Lines 6--7)? 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.
life and why the running current of streams and rivers must be made to yield their full benefit to the soil before they finally escape to the sea. We need to know the importance of big, mature 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 volume above the earth. In brief, it should be our goal to restore as much of the original 
as we can.
