"wake sb up"和wake up sb.都是叫醒某人,
如果是人名,就说wake up sb,如果是代词,就说wake sb up
Please wake up Charlie at six o'clock tomorrow.morning.
Please wake him up at six o'clock tomorrow morning.
另外,wake up,xxx!
是叫某人清醒,别糊涂了.
wake up,my dear friend!move on with your life.