Cone
A cone is formed by a set of line segments , half-lines , or lines connecting a common point , the apex , to all of the points on a base that is in a plane that does not contain the apex . 
<triplet> line segment <subj> half-line <obj> part of <subj> line <obj> part of <triplet> half-line <subj> plane <obj> part of <triplet> line <subj> plane <obj> part of <triplet> plane <subj> line <obj> has part