We have learned few interrogative words like kaha (कः), ke (के), kaa (का), kaaha (काः), kim (किम्), kaani (कानि) in previous lesson. Kaha (कः) means 'who' in masculine form and kaa (का) means 'who' in feminine form. saha kaha? (सः कः)? means 'who is he?' and saa kaa? (सा का)? means 'who is she?'.