Syntax

Syntactic actants

Actant 1: whose abdomen it is
(a) Genitive
(b) Possessive
Живот больного был неестественно вздут. The patient's abdomen was unnaturally distended.
Он выпятил свой живот. He stuck out his belly.
NB When the word живот functions as a subject and does not have a descriptive modifier, the construction живот у + Genitive is often preferred to (a) and (b), above:
Живот у больного был неестественно вздут. The patient's abdomen was unnaturally distended.