Psychologists recommend not to draw conclusions about a person’s intelligence by the manner of his writing and the mistakes made. But the texts say enough about a person to form an opinion about him. Moreover, nowadays people write more than before, Life today is generally defined by words – these are posts and comments on social networks, and emails, and messages in instant messengers, etc. Having made a grammatical error, we doom ourselves to a dismissive attitude , since the interlocutors, most likely, will notice it and draw a conclusion about the intellectual characteristics of the author of the letter. Especially in the labor market.