Indention doesn't work for if command [on hold]

As mentioned above here is the code:

 >>> if 10>5:   print("F")
     print("WORKS")
     SyntaxError: unindent does not match any outer indentation level

I tried to respect the "4 spaces" rule, but it always doesn't work. Also if I press "Enter" two times, it begins to run the program instead of letting me add more code to it. I usw Python 3.5.1 with the IDLE-Shell.