a baseball thrown with little velocity when the batter is expecting a fastball
双语例句
用作名词 (n.)
He'll throw the fastball inside off the plate to set up his off-speed pitches, and he will use it up in the zone with two strikes. 他会将他的快速球投进好球袋内角以便设定他的变速球，两好球后会利用好球带上方。
