Baseball is a bat-and-ball game played betweentwo opposing teams who take turns batting(击球) andfielding(投球).The game proceeds when a player onthe fielding team(防守队) , called the pitcher, throws aball which a player on the batting team (进攻队) triesto hit with a bat. The objectives of the batting team areto hit the ball into the field of play, and to run thebases — having its runners advance counter-clockwisearound four bases to score what are called "runs".

A run is scored when a runner legally advancesaround the bases in order and touches home plate (theplace where the player started as a batter). The teamthat scores the most runs by the end of the game is thewinner.
Baseball evolved from(由.….演变而来) older bat-and-ball games already being played in England bythe mid-18th century. This game was brought byimmigrants to North America.