Your goal with this puzzle is to get the bridge across the way to drop down. To do that, you're going to need to go through the door that is in between the stones.

If you'll notice, before you do anything at the very left of the room in the corner there's an opening that will show you the first answer. As you step on the pressure plate in the middle of this room, it will hide/reveal various parts of the puzzle. Each answer corresponds with the puzzle piece that is in the same location (i.e. leftmost, second from the left, etc.). Once you figure that out, it's a piece of cake.