In order to learn a foreign language well, it is necessary to overcome the fear of mistakes. If the primary goal of language use is communication, then mistakes are secondary considerations that may be dealt with gradually as awareness of those mistakes increases. On the other hand, students should not ignore their mistakes. The language learner may observe how native speakers express themselves, and how native expressions differ from the way the learner might say them. For example, a Spanish speaker who has been saying "I do it. " to express willingness to do something in the immediate future, could, by communicating with native speakers of English, observe that native speakers actually say "I’ll do it. " This difference can serve as a basis for the student to change his way of using the present tense in English. But a student who is unwilling to communicate in the first place would lose this opportunity to learn by trial and error.
According to the passage, foreign language students should not worry too much about mistakes because ______.