How do you get past the green vines on Harry Potter years 1-4 for ps3?

Remember at the end of the 1st Harry Potter movie when Ron didn't relax from the devil's snare? Hermione remembered that the devil's snare hates light... so use your lumos spell on the devil's snare (green vine looking things) and it will go away. If you didn't learn lumos yet go to where Flitwick's rooms are and go into the one where you learn the lumos spell.