Few areas have produced more debate in the field of English language learning than that of grammar instruction. What most language teachers agree on is that at some point language learners fare far better if they develop a firm grasp of the working rules that govern the use of the English language.
Where language professionals might differ is in “how” to teach grammar. Traditional methods initially used to teach Latin and Greek, consisted of learning grammar tables and rules by rote, and included a lot of painful repetition, which students rarely remember fondly. As for their effectiveness, since 17th & 18th-century learners were never expected to actually speak these ancient languages, it’s hard to say. Most would certainly remember verb conjugations for the rest of their lives!
With the popularity of modern languages such as English and the possibility of actually being able to speak the language being learned, methods gradually changed, albeit surprisingly slowly. Nowadays, a more communicative approach is favored in most language learning classrooms, and the emphasis on a precise knowledge of grammar is much more relaxed.