题目内容
14．The forest guards often find campfires that have not been________completely.
A．turned down B．broken down C．put out D．put off
C
同步练习强化拓展系列答案The African elephant, the largest land animal remaining on earth, is of great importance to African ecosystem(生态系统). Unlike other animals, the African elephant is to a great extent the builder of its environment. As a big plant-eater, it largely shapes the forest-and-savanna(大草原) surroundings in which it lives, therefore setting the terms of existence for millions of other animals that live in its habitat.
It is the elephant’s great desire for food that makes it a disturber of the environment and an important builder of its habitat. In its continuous search for the 300 pounds of plants it must have every day, it kills small trees and under-bushes, and pulls branches off big trees. This results in numerous open spaces in both deep tropical forests and in the woodlands that cover part of the African savannas. In these open spaces are numerous plants in various stages of growth that attract a variety of other plant-eaters.
Take the rain forests for example. In their natural state, the spreading branches overhead shut out sunlight and prevent the growth of plants on the forest floor. By pulling down trees and eating plants, elephants make open spaces, allowing new plants to grow on the forest floor. In such situations, the forests become suitable for large hoofed plant-eaters to move around and for small plant-eaters to get their food as well.
What worries scientists now is that the African elephant has become an endangered species. If the elephant disappears, scientists say, many other animals will also disappear from vast areas of forest and savanna, greatly changing and worsening the whole ecosystem.
【小题1】What does the underlined phrase “setting the terms” most probably mean?
| A．Improving the quality. |
| B．Deciding the conditions. |
| C．Fixing the time. |
| D．Worsening the state. |
| A．giving examples |
| B．showing the effect and then explaining the causes |
| C．pointing out similarities and differences |
| D．describing the changes in space order |
| A．Forests and savannas as habitats for African elephants. |
| B．The eating habit of African elephants. |
| C．Disappearance of African elephants |
| D．The effect of African elephants’ search for food |
| A．They are home to many endangered animals. |
| B．They are attractive to plant-eating animals of different kinds. |
| C．They result from the destruction of rain forests. |
| D．They provide food mainly for African elephants. |
Along the river banks of the Amazon and the Orinoco there lives a bird that swims before it can fly, flies like a fat chicken, eats green leaves, has the stomach of a cow and has claws (爪) on its wings when young. They build their homes about 4.6m above the river, an important feature (特征) for the safety of the young. It is called the hoatzin.
In appearance, the birds of both sexes look very much alike with brown on the back and cream and red on the underside. The head is small, with a large set of feathers on the top, bright red eyes, and blue skin. Its nearest relatives are the common birds, cuckoos. Its most striking feature, though, is only found in the young.
Baby hoatzins have a claw on the leading edge of each wing and another at the end of each wing tip. Using these four claws, together with the beak (喙), they can climb about in the bushes, looking very much like primitive birds must have done. When the young hoatzins have learned to fly, they lose their claws.
During the drier months between December and March hoatzins fly about the forest in groups of 20 to 30 birds, but in April, when the rainy season begins, they collect together in smaller living units of two to seven birds for producing purposes.
【小题1】What is the text mainly about?
| A．Hoatzins in dry and rainy seasons. |
| B．The relatives and enemies of hoatzins. |
| C．Primitive birds and hoatzins of the Amazon. |
| D．The appearance and living habits of hoatzins. |
| A．they look like young cuckoos |
| B．they have claws on the wings |
| C．they eat a lot like a cow |
| D．they live on river banks |
| A．They had claws to help them climb. |
| B．They could fly long distances. |
| C．They had four wings like hoatzins. |
| D．They had a head with long feathers on the top. |
| A．To find more food. | B．To protect themselves better. |
| C．To keep themselves warm. | D．To produce their young. |