Knowing a language means knowing the culturally connoted way of reading the world linked to it. For this to be part of the learning of second and foreign languages, it is necessary that teaching not be limited to grammatical notions (morphological and syntactic rules) and vocabulary, but also includes pragmatic and cultural aspects. In fact, even if we were able to formulate a "grammatically correct" phrase in a certain language, we could still communicate an incorrect message, leading to a misunderstanding.

Below (from Kecskes, 2014) is a case of misunderstanding between a Chinese speaker, Lee, who is learning English, a language in which he does not yet fully master the pragmatic-discursive dimension.

Lee: Could you sign this document for me, please?

Clerk: Come again?

Lee: Why should I come again? I am here now.

The clerk asks Lee to repeat, but using an expression that has developed a metaphorical and conversational meaning. In other words, "Come again?" should be understood as "Excuse me? Can you repeat again? "and no longer with its literal meaning. Unfortunately, Lee does not know this discursive use and the communication is not successful: Lee does not repeat his first statement but rather, probably annoyed, asks for clarification on why he should come back to a place where he already is.

For successful communication, "pragmatic errors" of this type can be more risky than those concerning vocabulary and grammar: if Lee had made a mistake in choosing a word (for example he had said write instead of sign) or the form of the pronoun (and, for example, said to I rather than to me), communication would probably have succeeded anyway.