问答题Today’s policemen in large cities throughout the world rely on modem inventions to help them in their work. In most places motor scooters and police patrol cars have done away with the need to patrol on foot or on horseback. Policemen use telephones, conveniently located throughout their districts, to make immediate contact with headquarters. Radio, television, and computers help to speed the work of the modem force. Even boats and helicopters are part of the equipment of metropolitan police departments. New technical inventions are widely used to fight crime and speed the solution for criminal cases. Electronic computer reduce from hours to minutes the time spent in searching for fingerprints. Witness’s descriptions of a criminal are coded and fed into a computer. The machine then sorts through the picture file of known criminals and selects the name and photograph of the most likely suspect. Lie detectors are used to uncover the truth.

问答题Petroleum is essentially a nonrenewable natural resource, an almost useless mixture comprised of very useful substances. It exists underground in liquid, solid, semisolid, and gaseous states. The name petroleum is derived from the Latin words petra and oleum, meaning rock oil . Created only by nature but exploited by man, petroleum is a nonrenewable resource because people consume it approximately one million times faster than nature can create it. Timber is a renewable natural resource; it can be harvested, replanted, and then reharvested in a few decades. In a sense, petroleum seeds are being planted today because the natural processes that create petroleum occur continuously. However, the results cannot be harvested for many millions of years. The petroleum that man harvests today was planted 30-6,000 million years ago! That is why petroleum is considered nonrenewable.

问答题Water problems in the future will become intense and more complex. On the one hand, our increasing population will tremendously increase urban wastes, primarily sewage. On the other hand, rapidly expanding industries which involve more complex chemical processes will produce larger volumes of liquid wastes, and many of these will contain chemicals which are noxious. To feed our rapidly expanding population, agriculture will have to be intensified. This will involve ever-increasing quantities of agricultural chemicals. From this, it is apparent that drastic steps must be taken immediately to develop corrective measures for the pollution problem. There are two ways by which this pollution problem can be dwindled. The first relates to treatment of wastes to decrease their pollution hazard. This involves the processing of solid wastes prior to disposal and the treatment of liquid wastes, or effluents, to permit the reuse of the water or minimize pollution upon final disposal. A second approach is to develop an economic use for all or a part of the wastes. Farm manure is spread in fields as a nutrient or organic supplement. Effluents from sewage disposal plants are used in some areas both for irrigation and for the nutrient supplement contained. Effluents from other processing plants may also be used as a supplemental source of water. Many industries, such as meat and poultry processing plants, are currently converting former waste products into marketable byproducts. Other industries are exploring potential economic uses for their waste products.

问答题It was one of those days that the peasant fishermen on this tributary of the Amazon River dream about. With water levels falling rapidly at the peak of the dry season, a giant school of bass, a tasty fish that fetches a good price at markets, was swimming right into the nets being cast from a dozen small canoes here. But hovering nearby was a large commercial fishing vessel. The crew on board was just waiting for the remainder of the fish to move into the river’s main channel, where they intended to scoop up as many as they could with their efficient gill nets. A symbol of abundance to the rest of the world, the Amazon is experiencing a crisis of overfishing. As stocks of the most popular species diminish to worrisome levels tensions are growing between subsistence fishermen and their commercial rivals, who are eager to enrich their bottom line and satisfy the growing appetite for fish of city-dwellers in Brazil and abroad. In response, peasants up and down the Amazon, here in Brazil and in neighboring countries like Peru, are forming cooperatives to control fish catches and restock their rivers and lakes. But that effort, increasingly successful, has only encouraged the commercial fishing operations, as well as some of the peasants’ less disciplined neighbors, to step up their depredations. The industrial fishing boats, the big 20- to 30-ton vessels, they have a different mentality than us artisanal fishermen, who have learned to take the protection of the environment into account, said the president of the local fishermen’s union. They want to sweep everything up with their dragnets and then move on, benefiting from our work and sacrifice and leaving us with nothing.

问答题I was up the next morning before the October sunrise, and away through the wild and the woodland. The rising of the sun was noble in the cold and warmth of it; peeping down the spread of light, he raised his shoulder heavily over the edge of grey mountain and wavering length of upland. Beneath his gaze the dew-fogs dipped, and crept to the hollow places; then stole away in line and column, holding skirts, and clinging subtly at the sheltering comers where rock hung over grassland, while the brave lines of the hills came forth, one beyond other gliding. The woods arose in folds, like drapery of awakened mountains, stately with a depth of awe, and memory of the tempests. Autumn’s mellow hand was upon them, as they owned already, touched with gold and red and olive, and their joy towards the sun was less to a bridegroom than a father.