Too long time to learn a serious problem because it affects students. They will know, exhausted, sleepy and distracted. So, take too long to learn to make efficient learning decreased.
Time to learn too long is a serious problem because it affects students. They know there are no concentrate, aches and a drowsy, so time to study for too long will cause reduced learning efficiency.
Time to learn too long. It is a serious problem because it has affected students they know to be tired and sleepy, so there is no time to focus on the performance, it will be too long to learn.