To play HyperShanghai click on each of the pair of tiles that you wish to remove and those tiles will become highlighted. HyperShanghai will make sure that your choices are legal. When you have clicked on both of your choices the "Remove Tiles" button will become active. Clicking on this button removes the pair. If before you click the "Remove Tiles" button, you want to change your mind about your choices, click on the tiles again and they will become unhighlighted. You will then be able to make other choices.