One day, Drona was out with his students practicing archery on the camp grounds. He sees a bird perched on a tree. Turn by turn, he asks each of his students to aim at the bird. When each student has latched his aim, Drona asks him, what he can see? Everybody in his turn, including Yudhishtira and Duryodhana says that, he can see the bird, the branch, the tree and the sky. Drona is not impressed, and ask the student not to proceed killing the bird.