It has been frequently observed that even those who learn an L2 in the target
community for an extended period of time, such as in an immersion school or in a
natural setting where the target language is used, still produce grammatical errors of
some forms (Doughty & Williams, 1998). Having been exposed to the positive input
for a lengthy period of time, they may be fluent in the language but still show some
errors and traces of non-nativeness in their output. This observation allows us to
know that language learning does not occur automatically only by being exposed to
the language input. In addition, many research studies (e.g. White, 1991) have indicated
that positive evidence alone is not enough to allow L2 learners to discover the target
language system. Schmidt (1990) also argues that consciousness, of some form, plays
an active role in L2 learning and that L2 learning cannot take place without learners’
noticing of the input they are exposed to. Therefore, some scholars hypothesize that
L2 learners will do better if some of their attention has been drawn to language forms
in a communicative and meaningful context (Lightbown & Spada, 2006; Long & Robinson,
1998). Sharwood-Smith (1993) also agrees that learners’ consciousness should
be raised, and one way to do this is to enhance the input, making it salient enough for
the learners to notice so that they can acquire it later.