Though in the past hundred years people have benefited enormously from modern inventions and technology, not all the changes are positive. For example, as people enjoy nuclear energy which is almost pollution free, they have also become more likely to suffer from the dangers of misuse or accidental breakdown of the nuclear reactor. The atomic bomb and Chernobyl are the two examples.

In addition, the side products in the process of improving the quality of our life are becoming out of control. For instance, our dependence on fossil fuel has caused the problem of global warning and acid rain. Emissions from car exhausts and factory chimneys have polluted the air to such an extent that hundreds of thousands of people die of respiratory diseases every year. More examples include the growing number of casualties because of car accidents, soil decay and water contamination due to the overuse of fertilizers and pesticides. And we cannot ignore the alienated interpersonal relationships as a result of lack of communication caused by increasingly faster life pace in the modern world.

In spite of all these undesirable changes, mankind will continue to strive for a better life. These negative changes are inevitable but many things are being done to curb their effects.