本程序模拟一个打字练习过程，从工作窗口的上端每隔一段固定时间就产生数个随机的写着字母的小球，练习者用键盘键入字母，如果键入字母和屏幕上任何的字母相同，该小球就小区，同时计算得分等。-This procedure simulated a practice typing process, from the top of every window, a fixed period of time has resulted in a few random letters written small bal