听力原文： Television in America gives people the choice of many different programs on many different channels. However, many people today are criticizing the quality of the programs. According to these critics, there are too many programs that only entertain there are not enough interesting programs that give information about the world around us. Perhaps the lack of serious programs is the fault of the commercial television system, not the fault of the people who own or who control the television stations. Television in America depends on money of people who advertise their products on television. Therefore, television stations need to attract advertisers. The programs which attract advertisers are, of course, the programs which have large audiences. And the programs which attract large audiences are usually programs with lots of entertainment and action. Programs about serious subjects, for instance, medicine, science, or history, are not very popular, so advertisers do not buy commercial time during programs like these. The commercial system, therefore, has a great influence on the kind of programs that television stations decide to show. Why do many people criticize TV programs in the U. S.?