Determining Factors in Distinguishing between Landmark & Trajector and Different Kinds of Landmark

Understanding situational relationship between things and their location in the outer world is the primitive and at the same time among the basic cognitive achievements of man kind, which is acquired from early childhood. On the other hand, prepositions are linguistic devices used for the linguistic codification of the situational relationship between things and their special situation in the outer world. This paper is an attempt to introduce the concept of Landmark and Trajectory, considering the concept of Perspective within the cognitive framework, different kinds of relationship between Landmark and Trajectory and the fact that these relations can be used in abstract cases. In the latter case we face the expression Imagery Schema. Authors have used their intuitions in considering the degree of naturalness of linguistic structures and have found out that factors like size of objects,movement or steadiness, fore grounding and back grounding are determining factors in considering a linguistic element as the Landmark or Trajectory in linguistic structures. These factors are those used by children in early stages of cognitive processingwhich have a close relationship with visual perception.