Singhasana (Lion pose)
     The shape of this asana is like a lion, hence the name.
1. Sit on the heels with the knees underneath.
2. Place the palms next to the knees.
1. While exhaling, hang the tongues out from the mouth.
2. Exhale with full force, making the sound "aaa" so that the face and chest become red.
  Thirty seconds up to three minutes.
It makes the whole body active, makes the voice sweet and improves clarity of speech.
It also improves eyesight.