‘X zài Y xiàbian’ (X is under Y) (e.g., Qiú zài zhuōzi xiàbian) (The ball is under the table): The compound position noun ‘Y xiàbian’ (under Y) refers to the bottom or the lowest part of the reference object, or the domain/space projected downward from the bottom or the lowest part of the reference object. ‘X zài Y xiàbian’ expresses two spatial relations, one is that the located object is under, but has contact with the lowest part of the reference object, for instance ‘Bǐ zài shū xiàbian’ (The pen is under the book), the other is that the located object occupies a position in the domain/space projected downward from the lowest part of the reference object. In this sense, the located object has the spatial relation of inferiority to the reference object. For instance:
Qìtǐng xiàbian guàzhe yī gè dà héngfú guǎnggào..
(Under the blimp was hanging a huge horizontal advertisement streamer.)
Zhuōzi xiàbian dūnzhe yī zhī māo.
(Under the table was sitting a cat.)
Shān xiàbian shì yī piàn càidì.
(At the foot of the hill is an expanse of vegetable fields.)
The big horizontal advertisement streamer hanging from the blimp has some coincidence or contact with the lowest part of the blimp in (1a), but the cat in (1b) only occupies a space projected downward from the lowest part of the table, while in (1c) ‘shān xiàbian’ refers to a space or a place that is under the top of the hill.
 Loar, J. K. (2011). Chinese syntactic grammar: functional and conceptual principles. New York: Peter Lang.