雅思口语天天练：一言既出 驷马难追

　　1. A single flower does not make a spring. 一花独放不是春，百花齐放春满园。

　　2. To go beyond is as wrong as to fall short. 过犹不及。

　　3. A young idler, an old beggar. 少壮不努力，老大徒伤悲。

　　4. A word spoken is past recalling. 一言既出，驷马难追。