How do you teach keldeo secret sword Pokemon white 2?

To teach Keldeo the move Secret SWord in Pokémon White 2, you need to take it to the Hidden Grotto located in the area where it was first encountered. Once there, you can select Keldeo and interact with the special pedestal. After that, Keldeo will learn Secret SWord, which is a powerful Fighting-type move. Ensure Keldeo is in its Resolute Form for the move to be taught.