If sharingan can copy ninjutsu [except kekei genkei] just like Kakashi copied more than 1ooo tech....and like Sasuke copied Lee's [primary lotus] in the first chunnin exam and Kakashi copied the rosengan and showed to naruto when he was about to start training for FRS...so why Sasuke didn't copy the rosengan.he knew that rosengan is powerful than Chidori when he and naruto faught on the top of the Hospital......so is there any special condition to copy the jutsu with sharingan?? 