<p class="ql-block"><span style="font-size: 22px; color: rgb(255, 138, 0);">18.Which of the following statements concerning botany is true?</span></p><p class="ql-block"><span style="font-size: 22px;">A) Botany is a very ancient learning.</span></p><p class="ql-block"><span style="font-size: 22px;">B) People in the Stone Age know a lot about plants.</span></p><p class="ql-block"><span style="font-size: 22px;">C) People in the Stone Age know little about plants.</span></p><p class="ql-block"><span style="font-size: 22px;">D) Pre-industrial societies have little insights about plants.</span></p><p class="ql-block"><br></p><p class="ql-block"><span style="font-size: 22px; color: rgb(255, 138, 0);">19.Which of the following is true?</span></p><p class="ql-block"><span style="font-size: 22px;">A) People who live in Amazon tribes don't think plants are the basis of the food pyramid.</span></p><p class="ql-block"><span style="font-size: 22px;">B) People who live in Amazon tribes don't regard botany as a special branch of knowledge.C) People who live in Amazon tribes know all the properties of plants in the jungle.</span></p><p class="ql-block"><span style="font-size: 22px;">D) People who live in Amazon tribes give some special names of botany.</span></p><p class="ql-block"><br></p><p class="ql-block"><span style="font-size: 22px; color: rgb(255, 138, 0);">20.What was the first great step in a new association between humans and plants?</span></p><p class="ql-block"><span style="font-size: 22px;">A) Agriculture in the industrialized world.</span></p><p class="ql-block"><span style="font-size: 22px;">B) Cultivated crops.</span></p><p class="ql-block"><span style="font-size: 22px;">C) The association between roses and humans.D) The discoveries of certain grasses.</span></p><p class="ql-block"><br></p><p class="ql-block"><br></p><p class="ql-block"><br></p><p class="ql-block"><br></p><p class="ql-block"><span style="font-size: 22px;"></span></p><p class="ql-block"><span style="font-size: 22px;"> Botany, the study of plants, occupies a peculiar position in the history of human knowledge. It is impossible to know today just what our Stone Age ancestors knew about plants, but from what we can observe of pre-industrial societies that still exist, a detailed learning of plants and their properties must be extremely ancient. Plants are the basis of the food pyramid for all living things. They have always been enormously important to the welfare of people, not only for food, but also for clothing, weapons, medicines, shelter, etc.</span></p><p class="ql-block"><span style="font-size: 22px;"> Tribes living today in the jungles of the Amazon recognize literally hundreds of plants. To them, botany, as such, has no name and is probably not even recognized as a special branch of "knowledge" at all. Unfortunately, the more industrialized we become, the further away we move from direct contact with plants. Yet everyone unconsciously has an amazing amount of botanical knowledge, such as recognize a rose, an apple, or an orchid. Our Neolithic ancestors, living about 10,000 years ago, discovered that certain grasses could be harvested and their seeds planted for richer yields the next season. This was the first great step in a new association between plants and animals. Grains were discovered and from them flowed the marvel of agriculture: cultivated crops.</span></p><p class="ql-block"><span style="font-size: 22px; color: rgb(237, 35, 8);">答案：ABB</span></p>