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If you read through the material on the Forum, you will note that many, many questions that students ask are reducible to "Is this sentence grammatical?" So a teacher who didn't know grammar would not be able to answer most of his students' questions. To be grammatical is, to put it simply, to be correct. A teacher who doesn't not know which combinations of words are correct in English and which are not -- in other words a teacher who does not know the grammar of English -- should definitely not be teaching English. Compare this to a mathematics teacher who does not know the rules of mathematics. I don't suppose such a person should be teaching math!
CJ
If you read through the material on the Forum, you will note that many, many questions that students ask are reducible to "Is this sentence grammatical?" So a teacher who didn't know grammar would not be able to answer most of his students' questions. To be grammatical is, to put it simply, to be correct. A teacher who doesn't not know which combinations of words are correct in English and which are not -- in other words a teacher who does not know the grammar of English -- should definitely not be teaching English. Compare this to a mathematics teacher who does not know the rules of mathematics. I don't suppose such a person should be teaching math!
CJ
Comments
Study the following examples:
My father smokes. The tense in this sentence tells you about a habitual action.
My father is smoking. This sentence tells the others that my father is doing something at the moment. Activity in progress.