The simplest kind of reference frame. It involves just a (primary) reference object and employs the intrinsic geometry of this reference object in order to locate the figure. For instance, in an utterance such as: The grocery store is next to the office building, the office building has an intrinsic front, back and sides to which the speaker appeals in describing the location of the grocery store. Therefore, this type of reference frame is ground- (or reference-object) based.