Three tasks of language learning

So, here is the most generic entry into how I think about language learning:

Three general tasks enable a student to learn a language, they are: massive amounts of input in the language (exposure to the language), massive amounts of output in the language (opportunity to use the language), and plenty of opportunity to adjust understandings and utterances to closer match those of native speakers. Though these three tasks seem fairly obvious, it is surprising how routinely they are misunderstood, or misapplied. The third task--opportunity to adjust understandings and utterances--is critical, but many teachers overdose on an ugly step-sister to this task: the dreaded grammar drills. Such drilling before a student has a sort of feel for what is being drilled is a waste of time and effort.