The duplo is a debate in verse. Those who planned to do the duplo did a lot of practice in the rice fields or resting under the tree. The participants usually searched for verses from nearby towns, and gave up their fighting roosters or dumalagas in exchange for verses.

The duplo was held during the prayers said for the dead. It was also held during the first anniversary of the death of a person. The widow or survivors of the deceased would usually invite some young ladies and gentlemen from their barrio or neighboring ones to perform the duplo.

The Balagtasan is a modified form of the duplo. It is a poetic joust between two poets. The first balagtasan was held on April 6, 1924, at the Instituto de Mujeres, a school for young women located on the Tayuman Street in Manila. The two poet combatants were Jose Corazon de Jesus and Florentino T. Collantes, two young poets then.

If you like to read more, the source of this was Teodoro E. Gener's lecture, Institute of National Language, Manila, Philippines, March 29, 1944 and his other lecture in June, 1948.