Do you know what DK is?

These days, my Nateon nickname is 'DK is difficult....' DK is quite ambiguous. But what I mean is "Dakchigo Kongbuhaja", ed ist "Shut up and study."
I'll introduce you how this is came out. I was talking at late night with my best friend, Seo Dong-min. He is a freshman of department of mathematics education, Korea University. The subject of story was his being lethargic. The reason was playing too much. He enjoyed his playing with his friends very much, but few days before a thought flashed across his mind: what the hack I am doing? Was I born to just play?
So he decided to study as he did in 12th grade. I, also failed to do something again and again(you know what it is), thought like this: What on earth I am doing now like a crazy guy? Therefore, we determined to study hard and get a very, very good grade from this week. But it's fairly tough...but I'll try my best!