The question to teach or not to teach grammar has always been present for no clear answer could ever be provided; both sides, the advocates and opponents of teaching grammar, keep producing evidence to buttress their own views towards this issue. The former believe that grammar is an important component in language teaching, whereas the latter believe that language can be learnt holistically through the context without explicit instruction.
What motivated me to address this question, whether grammar is important in second language teaching, is the claim of some ioneer linguists, Krashen for example mentioned in Ellis, 1985: 230, who maintain that learned knowledge can not convert into acquired knowledge and that consciousness raising of grammar is neither a sufficient nor a necessary condition for mastery of another language. I was taught English in a country where English is a foreign language and I was taught explicit grammar throughout all of my study stages.
I can assert that the teaching of grammar could be of great support especially when interacted with communicative context even in later years. I can still retain rules that help me speak properly and accurately and I can claim by now that all the grammatical knowledge I learned in my study years has already converted into acquired knowledge. It is beyond doubt that ignoring such rules would be an obstacle in forming and uttering the simplest sentences in English.
Native speakers of English, even when they have not studied grammar, can form accurate grammatical sentences because they unconsciously internalize grammar rules while they are growing up. There is a general consensus among learning theorists, educational psychologists, and teaching professionals that language is “a rule-governed behaviour and it is a rule-bound system in both standard and non-standard varieties and in both spoken and written modes” (Brindley, 1996: 224). Cook, 2001: 19 states that grammar is considered by many linguists “the central area of language around which other areas such as pronunciation and vocabulary revolve”.