Don't____ ____ the computer．

下列各命题正确的是（　　）

    Baseball is one of the favorite sports in the USA. Children play baseball in sports fields or parks.

    At summer picnic, there is often an informal baseball game. Boys and girls, young and old take turns to bat. There are nine players on each team.

    The baseball season goes from April to September. During this time, baseball matches are showed on TV and members of the important baseball teams become America's heroes (英雄). At the end of the season, the two top teams play against each other. Many baseball fans go together to watch the game. Millions of others listen to the radio or watch the television. People seem to talk only about the game. Even long after it is over, they still talk about the result and the players.

    American football is perhaps the most popular sport in the USA. The football season begins when the baseball season ends. More people are interested in football than baseball. When there is an important game, thousands of people sit beside radios or in front of television sets to get the result.

下列关于水的说法中，不正确的有：____（填序号）．

①水是由氢元素和氧元素组成的化合物     

②清澈、透明的泉水是纯净物

③合理施用农药、化肥，以减少水体污染   

④将活性炭放入硬水中可使其软化

⑤洗菜、洗衣后的水用来浇花、冲洗厕所