NOVELTY - The structure (101) has a set of primary cutting elements coupled to a blade, and extended along the blade in a direction parallel to a centerline of the blade. A secondary cutting element rotationally leads the primary cutting elements in a direction of intended rotation of the structure, and is coupled to the blade proximate to a leading surface of the blade. The secondary cutting element comprises one of a rubbing surface and a cutting surface, where exposure of one of the primary cutting elements is greater than exposure of the secondary cutting element.    USE - Fixed and rotatable cutting structure for use with a downhole/earth boring tool e.g. reamer (claimed) such as expandable reamer, for enlarging a subterranean borehole of wells e.g. oil wells, gas wells and geothermal wells, during a drilling operation in a subterranean formation. Can also be used for a fixed reamer, bi-center bit and eccentric bit, and for an earth-boring rotary drill bit, roller cone bit, core bit, mill tool and hybrid bit.    ADVANTAGE - The structure is more robust in handling drilling and reaming dysfunctions e.g. vibrations caused by operations of the reamer following a pilot bit, during downhole operations. The primary cutting elements are positioned proximate to the centerline or trailing surface of the blade to pivot the reamer such that a rotationally leading portion of the blade protects the blade and reamer so as to reduce potential damage caused to adjacent cutting structures.    DETAILED DESCRIPTION - The primary cutting elements and the secondary cutting element are polycrystalline diamond compact (PDC) cutters. INDEPENDENT CLAIMS are also included for the following:    (1) a reamer for use in a subterranean borehole    (2) a method for enlarging a subterranean borehole.    DESCRIPTION OF DRAWING(S) - The drawing shows a side view of a reamer including a set of fixed and rotatable cutting structures.    Expandable reamer apparatus (100)    Fixed and rotatable cutting structure (101)    Tubular body of expandable reamer apparatus (108)    Lower sub (109)    Distal end of tubular body (190)    Proximal end of tubular body (191)