Studying and me

Studying is very difficult for me. Because I'm very careful while I'm studying. If teacher told to me "A", I think "That's really correct?" first. When I got it cleary and got involved the knowledge, then if I could use it naturally, my study about that will finish. But as usual, the distance between here and the goal is so long. My head quest to myself "Is it true?". So, I'm not good at studying or learning in those velocity. But I can remember it long as I think it again and again. That's studying for me. So, I think JUST STUDYING is lazy and not good for all. Why don't you thinking again?