How do you break out of a monsters grip with a controler in monster hunter tri

if you mean by the classic you basically move the control stick (the one you move with) a lot till the pink bar disappears and for the nunchuck and wii mote wave them about till you break but the best way to get a monster off you is to carry some dung bombs on you and throw it in its face when you get pinned down you don't loss any health if you throw it when its about to take the first bite.