Some embodiments include methods of recessing multiple materials to a common depth utilizing etchant comprising C4F6 and C4F8. The recessed materials may be within isolation regions, and the recessing may be utilized to form trenches for receiving gatelines. Some embodiments include structures having an island of semiconductor material laterally surrounded by electrically insulative material. Two gatelines extend across the insulative material and across the island of semiconductor material. One of the gatelines is recessed deeper into the electrically insulative material than the other.