studying makes me sleepy

i noe.. from my title u can guess how piggy i am.. lolx.. serious, whenever i study, it will makes me sleepy for no reason. But when i do some other stuffs, i will not get sleepy like chatting on msn / playing games / surfing the net/ blog shopping.... seriously don noe y. i tried eating sweets, chocolate but no use will onli make me fatter.. after so long, i am still stuck at chapter 1.. still have three more chapters to go.. 100 more pages.. muz use all the brain cells in my brain.. lolx.. not all, but at least some. okay back to studying. Blog juz to make me not fall asleep back again.. sitting beside my bed is tortue.. make me feel like lying down and slp.. LOL.. tmr exam starts at 12, therefore have to wake up extra early if i want to study:( jia you to me once again.. anyway todae exam kina sux... maybe coz i did not study hard enough.. muz be for sure.. will try my best next time.. heng tis exam onli contain a little bit of percent.. phew..