Need help with drag and drop game, Urgent!

Hi I have created a drag and drop game, the drag and drop is working alright however once the right word has been placed in the box, and moves on to the next question the previous correct answer stays where it was placed, how can i get it to snap back to its original location? Also when the right word is draged in to the the white box i want it to snap into place in that box so it fits in there.

Also if you have any other thoughts and advice on how i can improve on this please email me thanx

Can someone please help, my .fla file can be found here:

http://www.freshlemon.co.uk/timeline.fla

http://www.freshlemon.co.uk/timeline.fla.zip

thanx