In most studies, the ability of adult native speakers to use and understand connectives is taken for granted. In this presentation, I will challenge this assumption and show that important individual differences exist. I will focus on connectives that are mostly used in the written mode, such as however and therefore in English. In a series of three experiments, I will show that a portion of teenagers and adults have a hard time using and understanding less frequent connectives, and that their level of competence is correlated with their degree of familiarity with the written mode, in other words their level of exposure to print. Taken together, these results plead in favor of developing more easily accessible resources to document correct uses of connectives across languages.