شرط
preferred label: condition @en
type: Concept
narrower: گزاره دو شرطی

زبان
preferred label: language @en
type: Concept
related: گزاره دو شرطی

قضیه
preferred label: theorem @en
type: Concept
related: گزاره دو شرطی

گزاره دو شرطی
related: قضیه
related: زبان مرتبه اول
related: زبان
broader: شرط
preferred label: biconditional statement @en
type: Concept

زبان مرتبه اول
preferred label: first order language @en
type: Concept
related: گزاره دو شرطی