Keldeo forme event in B2?

Question

My friend took part in the Keldeo event. He traded it from his Black to my Black, and I then traded it to my black 2 immediately after. How can I teach it secret sword in black 2? Is it even possible? If I trade it back to black 1 then can I teach it to him and change his forme in the new one? Please help me through this dilemma.

Answer 1

Keldeo can only learn the move in Pokémon Black and White via tutoring when the remaining Swords of Justice are also in the party. When the four are brought to the Moor of Icirrus, the trio will teach Keldeo the move. It can also be learned by Keldeo in the Pledge Grove in Pokémon Black and White 2, where learning the move allows Keldeo to change to its Resolute Forme.

http://bulbapedia.bulbagarden.net/wiki/Secret_Sword_(move)
http://bulbapedia.bulbagarden.net/wiki/Move_Tutor#Black_and_White