例句：

　　1、Sound travels better in water than in air.

　　聲音在水中比在空氣中傳播得快。

　　2、She looked round at the sound of his voice.

　　聽到他的聲音，她扭頭看了看。

　　3、This gives the design team a sound basis for their work.

　　這為設計組開展工作提供了堅實的基礎。

　　4、The first year provides students with a sound theoretical basis for later study.

　　第一年為學生以后的學習奠定堅實的理論基礎。

　　5、They had a wonderful time by the sound of it.

　　聽起來他們好像過得很愉快。