The authors discuss two fundamental goals of second language acquisition (SLA): using language grammatically and being able to communicate. They also mention the disagreement in SLA on whether to focus on teaching grammar rules or grammar as a skill. The authors propose a conceptual framework for teaching grammar that focuses on form, meaning, and use at three grammatical levels: subsentential, sentential, and suprasentential. They note that language is mutable and organic, and grammar should be explained through reasons rather than rigid rules.