A person who is fluent in a foreign language can easily teach it
Some people think that each person who knows foreign language well, can teach it.
Other belive that only people, who have special education can explain something, connected with language, to other people.
As for as my opinion is concerned, even if person knows foreign language well, he can not become a teacher for others people.
Firstly, I suppose that this person know only foreign language but the art of explaining he do not know as well, as language.
Even if he knows details and nicities of language, he simply will not able explain it.
Some people have not a tallent to be a teather.
More over, man, who speaks foreign language well, may be not communicative and sociable.
Also irritability and nervousness can prevent teaching.
Other people believe that if someone knows foreign language well, he can teach people, because the main is knowing language and all another are not necessary.
But I disagree with this point of view.
A lot of people are free only in speaking, but they do not know grammar and can not substantiate why he speak such, but not another.
They can not teach other absolutly right.
In conclusion, I want to say that it is not enough only to be fluent in foreign language for teaching other people.
There are necessary some qualities of man for it.