The development of science and technology makes our life more comfortable and convenient. However, scientists have created many problems, which are not easy to be resolved, such as air pollution, the deterioration of environment and the scarcity of natural resources, to which we must some solutions. Modern science and technology render people many advantages. Modern telecommunication shortens the distance between people and makes communication much easier. Internet is widely used now not only for collection of abundant information but also for correspondence. Email, the most effective communication device now, is becoming very popular. Besides, telephone and mobile phone make contact more convenient than before. Modern transportation, such as airplanes and high-speed trains make our journey smooth and fast. With the help of modern transportation, people can go everywhere they prefer to. The journey to outer space and other planets is not a dream any more. Rockets and space shuttles can help us realize the dream of space travel. Modern medicine prolongs peoples life and relieves patients of sufferings from many diseases. Cancer and AIDS are fatal to peoples health. Thanks to the endeavors scientists have made, these diseases become treatable. However, the process of scientific development also arouses many sever problems to our human beings. Internet, though widely used in modern communication, is easy to be destroyed by computer virus. Outer space exploration has produced much waste in the space. A tiny metal, a screw, for example can destroy a flying man-made satellite. Industrialization is making natural resources become scarce. Confronted with these problems, scientists are seeking prompt and feasible solutions. The development of science and technology bring abou
