. Xu?ng ti?n tr??c khi tr?n b?t ??u hay tham gia c??c trong khi tr?n thi ??u di?n ra.A rotating plan is often a program arrangement where personnel work working day shifts for just a time frame, then change to evening shifts for some time, and afterwards go back to Performing working day shifts.??i v?i nh?ng ng??i ch?i l?n ??u th?c hi?n tr??th??ng