The problem is there are staccato among legato and after I do the staccato, I continue staccato after it when it should be legato. I know it but it's hard for me to switch somehow. I can do it for several measures but then I forget about it again afterwards
i know what staccato is but what is regato? is that like playing notes normally and letting them ring?
That happens. You need to concentrate on what you are doing to not fall on these traps of automatic movements. I think the best way to help you learn to do that is practicing very slowly and deliberately. This you need to do at home, but the results you will see on the lessons.EDIT: Corrected your spelling mistakes
It's indeed these automatic movements that cause the problem. I'm practicing it very slowly at home now. The teacher complained one big problem is that I seem to resist him in class and cannot make the improvement soon enough, which I feel a bit wronged. I want to but just cannot do that immediately.