CNBLUE posted a photo of themselves working hard in preparation for their upcoming concert.

Recently, the band took to Twitter and wrote, "Everyone, we're having our last preparation for the concert! keke. Everyone, you have to be careful to not catch a cold. You have to spend all your energy at the concert... Haha. Look forward to our concert!!!", and uploaded a photo of the four members practicing hard.

A few hours later, Yonghwa uploaded photos of a picture he drew for the '2012 BLUE NIGHT', writing, "Everyone, it's Yonghwa keke. Everyone, I think I draw so well keke. It's getting cold, so be careful not to catch a cold~!". The picture he drew showed a purple-and-yellow butterfly with the words 'BLUE NIGHT' written on its wings.

The '2012 CNBLUE Live Blue Night in Seoul' will be held on December 15th and 16th at the SK Olympic Handball Gymnasium in Olympic Park.

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Source: CNBLUE's Twitter