right and left hand

i cant imagin my self useing my right hand as i use my left hand, in last thursday our teacher asked us to use our left hand if we are right handed and if we are left hand use the right , to be honst at first it was soo hard and i couldnt do the thing that i do it with my right hand , but i reallized that if i keep practicing i will get it . in my culuter the right hand is very importnat for us for many resons , we shake our hands by the right one , we used th right hand when we eate, and we used it when we point at any thing .