表达 word of mouth 直译过来是“嘴里说出的话”，指人与人之间传播信息时的口头传述方式，和文字传播是一组对立概念。该说法的形容词形式是加连字符的“word-of-mouth 口碑的，口口相传的”，多用于谈论广告、宣传和营销的商业语境中。人们在这个表达前常使用介词 by，意思是消息通过口头转述的方式 by word of mouth 传播开来。

例句

These days, food rating apps are becoming very popular. This is why many restaurants have started to put a high value on online word-of-mouth marketing.

如今，美食评论应用正广泛地普及开来。这就是为什么很多餐厅开始非常重视网络口碑的营销策略。

Folk tales are passed on by word of mouth, leaving no written records of who the authors might be.

民间故事是口口相传的，不会留存表明作者身份的文字记录。

It is said that in a digital world, social media has become the new word of mouth.

据说，在数字化的世界里，社交媒体已转变成口述信息的新平台。