Punctuation marks have special importance in bringing out the meaning of a text. Nonetheless, they are not normally taken into consideration in text production in foreign languages and therefore constitute a strong source of interference. This article analyses the use of a series of punctuation marks (hyphen, quotation marks, etc.) in French, German and Romanian, highlighting the differences and trying to give explanations for the abuse of several signs in texts in the different languages written by non-native and native authors. Evidence is given that the use of the punctuation marks in a foreign language following the norms of the mother tongue may produce misunderstandings on behalf of native readers. Furthermore, it can be shown that the prescriptive and descriptive grammars of the implied languages do not represent current tendencies of use.