I study in +2 medical . While studying I observed that so many people says to us study for at least 12 to 13 hours a day . But I think you should not do study according to those students who study for 12 or 13 hours a day . You should study according to you when you wants to do study when your mind allow you to gain knowledge. When your mind says no then leave. Then take a time and again strat . Readers you know you study for 12 to 13 hours and you got less marks in your exams and then you got hurt and said i do lots of efforts and i study for 12 to 13 hours a day then why I got less marks . You know guys study for 12 to 13 hours is your bad marks reason when you study with interest you remembered that thing in your exam but which you learn when your mind is gone overloaded guys everyone knows how many hours they can do study. Guys you know if you are interested in study then you can learn everything which you read in 2 to 3 hours maximum but when you are not interested so read hole day nothing is memorised . So do study when you wants to study when you can give your full efforts.