Mural Paintings in Durgapur

I have been trying to teaching what's the actual meaning of art in this 7 years. An ART never be a reserved knowledge I mean to say give you a example..My teacher said you u'll never use black tone when u painting a ripe mango.. It's not actual guide but at the same time if my teacher said just see how,when and where we can use the black color.. exactly it's a actual meaning of an art teacher.. U can contact with me to this no.. F ... less