In this section, we have identified the complexity of the second language learner's task and explored the ways in which learners typically go about it through examining interlanguage (ie the language learners produce and the assumed knowledge behind it). We have highlighted such features as:

• the domination of lexical items in early acquisition, with grammatical features such as verb and noun morphology typically missing;
  
  
• gradual grammaticization, illustrated by overgeneralization of grammatical regularities;
  
  
• stages of development, in some areas of grammar, which are the same for learners from different backgrounds, irrespective of whether they have received instruction;
  
  
• influence from knowledge of existing languages, but not always direct interference where there are differences with the target language.

Learners instinctively seem to draw on knowledge of existing languages, particularly those perceived as close to the target language. As teachers, we need to recognize that this can be a very positive strategy, even though it can also lead to some confusion and errors. But banning reference to other languages in the second language classroom, in particular the L1, seems to have little to commend it.

The idea that learners will learn any grammatical structure we teach them, so long as we teach it effectively, also seems to be challenged by the SLA research. Internal grammar - as opposed to the knowledge of 'chunks' - takes time to develop and while teaching may speed up the rate at which learners move through stages of development, and their accuracy in certain areas of the grammar, it does not seem able to alter the route, at least in the key areas which have been researched.

Thus, as teachers we need to understand that learners' errors may not represent willful laziness or inattention, but often demonstrate the stage of development which they have reached. Full grammatical accuracy and fluency in second language acquisition are hard to achieve and seem to require a combination of different learning processes: lots of opportunities for the learner's grammar to build up implicitly, practice of 'chunks' in order to increase fluency, but probably also explicit instruction as well.

In the second section of this module, we set out to characterize the possible learning processes that might be involved in second language acquisition.