Spatial concepts are relational. In conceptualizing spatial relationships, English and Chinese adopt two different strategies for encoding spatial relations. English uses prepositions to indicate spatial relationships; moreover, prepositions are used in relation to dimensional properties of the reference object concerned. For instance:
1a. There was a fly on the wall.
1b. There are worms in the wall.
In the case of (1a), the wall is viewed as an area or surface with two dimensions. This is implied by the meaning of the preposition ‘on’. ‘On’ also requires that there be some contact between the located object and the reference object, and the dependency between the two objects or entities is that of support, with the reference object supporting the located object. Thus the preposition ‘on’ has three implications: dimensionality, contact and support. In (1b), the preposition‘in’ implies that the reference object ‘the wall’ is viewed as three dimensional, and it also implies the inclusion or containment of the located object ‘worm’ in the reference object ‘the wall’ (Quirk et al. 1985).
 Loar, J. K. (2011). Chinese syntactic grammar: functional and conceptual principles. New York: Peter Lang.