美国斯坦福大学一位文学博士在新出版的书中指出，讲脏话其实并不是教育水平低下阶层的专利，上层阶级的大佬们也很喜欢讲脏话，讲脏话最少的是中产阶级人士。她还指出，大部分儿童在完全会讲话之前就已经会骂人了。此外，她还发现，讲脏话在生活中也是有一些实际用途的。比如，你不小心撞到脚趾的时候，骂一句脏话可以帮助你缓解疼痛，这在之前的研究中已有证明；同时，讲脏话还能帮助建立友谊，比如，几个工人在一起聊到他们的经理时，说说脏话可以增进感情，让彼此有归属感。这位博士的分析数据显示，一位普通的英语国家人士每天说的话里有0.7%带有脏字，也就是说，他们每说140个字，就有一个是脏字，这与第一人称代词的使用频率相当。
Using swearwords is often thought of as the preserve of the thoughtless and uneducated - but new research suggests that this may be nothing more than a myth.
A language expert has published a new book about the history of swearing, and discovered that the practice is a lot more common - and a lot less useless - than most people imagine.
Among Melissa Mohr's revelations are the fact that most children learn how to swear before they even know the alphabet, and that some swear words date back to the time of the Romans.
The author told Time that her book, Holy Sh*t: A Brief History of Swearing, sets out to correct some of the misconceptions held by many people about swearing.
While you might think that less educated working-class people are more likely to swear than others, in fact the upper classes are just as keen on blue language.
In contrast, the group least likely to use bad language is the middle class, according to Dr Mohr.
'This goes back to the Victorian era idea that you get control over your language and your deportment, which indicates that you are a proper, good person and this is a sign of your morality and awareness of social rules,' she said.
Additionally, many claim that swearing is a sign of mental laziness, but the evidence shows that it does in fact have some practical uses.
If you are subjected to acute pain such as stubbing your toe, swearing can be cathartic, providing relief from the agony - studies have shown that swearing sometimes has a genuine physiological effect on the body.
Swearing also helps to form social solidarity - for example, when workers use swear words while talking about their managers, it builds an 'in-group' which aids social and professional interaction.
Dr Mohr told Time that an analysis of the words used by an average English-speaking person over the course of a day reveals that around 0.7% of our language consists of swear words.
That means that one in 140 words we use is obscene - roughly the same proportion as the first-person plural pronouns such as 'we', 'us' and 'our'.
The surprising preponderance of swearing in everyday language explains why the majority of children know at least one swear word by the age of two.
Many toddlers not yet old enough to learn the ABC are so exposed to swearing that they use bad language themselves.
Dr Mohr, who holds a PhD in Renaissance literature from Stanford, has also revealed that swearing is nothing new.
But there are different trends in swearing down the centuries - for instance, in the Middle Ages scatological words were considered much less offensive, but religious oaths such as 'by God's bones' were believed to be so potent that they did physical harm to Jesus Christ.