练习15　　(1) Whatever its underlying reason, there is no doubt that much of the pollution caused could be controlled if only companies, individuals and governments would make more efforts. In the home there is an obvious need to control litter and waste. Food comes wrapped up three or four times in packages that all have to be disposed of; drinks are increasingly sold in bottles or tins which cannot be reused. (2) This not only causes a litter problem, but also is a great process by persuading many of us not only to buy things we neither want nor need, but also to throw away much of what we do buy. Pollution and waste combine to a problem everyone can help to solve by cutting out necessary buying, excess consumption and careless disposal of the products we use in our daily lives.