someone asked me this question! I would appreciate your comments...

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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!
When you know something. it will be easy for you to convey it to the others. Knowing English Grammar is somehow a must. The reason why is that teahcers are models whom the students imitate. Through English Grammar, we can understand and be understood when speaking. The way you use English correctly means that you can help the others understand you in a better way. Actions are viewed in the way English is used.

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.
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 CalifJim's reply was promoted to an answer.
How on earth does this - knowing grammar, and your eg., - actually help a person speak the language? Imagine we were leaning Urdu, do you think knowing the above would assist you in any way whatsoever if you were suddenly plunged into a foreign (Urdu speaking) environment?
I always thought that "compare" was always followed with the preposition "with". Peter N, Brisbane Australia
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