题目内容：
It is obvious that television has both advantages and disadvantages. In the first place, television is not only a convenient source of pleasure, but also a quite cheap one. For a family of four, for example, it is more convenient as well as cheaper to sit comfortably at home, with so many interesting programs available, than to go out for something else. There is no transport to arrange. They do not have to pay for expensive seats at the theatre, or the like, only to discover, perhaps, that the show is disappointing. All they have to do is to turn a knob, and they can see plays and shows of every kind, not to mention the latest current events. Some people, however, maintain that this is just where the danger lies. Those who watch television need do noting. They are completely passive and have everything presented to them without any effort on their part.
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