Or he just started learning spanish and learnt that one sentence to say to the media, as this was a planned event.
Or his language learning abilities are extraordinarily .. he learned how to correctly recite certain words from the Barca anthem after one quick few minutes coaching .. he had to learn the pronunciation once only for each word and then managed to say the entire anthem more or less correctly. Check his Barca taxi video.
It is clear that the kid is both smart and holds huge respect to towards the club