听力题 The history of plastics is longer than you might expect. In fact the first man-made plastic ever to appear on the market was made over a hundred years ago. It was discovered both by an Englishman and by an American in the same year. But it was the American who first manufactured it on a large scale during the 1860s. Everybody was excited by this new material which was so cheap to buy. Poor young men working in smoky cities were able to buy plastic collars. These collars were hard and uncomfortable. But they did not have to wash them. The poor young men could rub them clean every evening with soap and water. Poor mothers who had not been able to afford playthings for their children, were now able to buy them playthings made of plastic.