1.  Define generic and trademark as used in the article.

2.  What percent of U.S. product brand names become generic?

3.  What problem does a company have when its brand name becomes commonly used?

4.  List the products mentioned in the article for which companies lost the trademarks after they were too commonly used.

5.  Which companies have held onto the trademarks for their commonly used brand names?

6.  Name some other brands that are commonly used today, which were not mentioned in the article.