Definition of sustains:
(v) :
(transitive) To maintain, or keep in existence.
(v) :
(transitive) To provide for or nourish.
(v) :
(transitive) To confirm, prove, or corroborate; to uphold.
(v) :
To keep from falling; to bear; to uphold; to support.
(v) :
(transitive) To encourage or sanction (something).
(v) :
(transitive) To experience or suffer (an injury, etc.).