阅读理解。 Baseball is one of the most popular sports in the USA. Children play baseball in sports fields or inparks.At summer picnics,there is often an informal (非正式的) baseball . Boys and girls, the youngand the old  take  turns to bat (周球棒击球). Each team has nine players. The baseball season goes from April to September. During this time, baseball matches are shown on TV and members of the important baseball teams become America's heroes. At the end of the seasons, the two top teams play against each other. Many baseball fans go along to watch the .Millions of others listen to the radio or watch TV. People seem to talk only about the result and the players. American football is 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 , thousands of people sit beside the radios or in frontof the TV sets to get the result. 1. Where do children play baseball in America? _______________________________________ 2. How many players does each baseball team have? _______________________________________ 3. When does the baseball season go? _______________________________________ 4. What is the most popular sport in the USA? _______________________________________