Anchor: Structural steel is used primarily for the absorber, ductwork, and supports, and secondarily in miscellaneous components including reinforcement of existing structures at a facility.
Entailed: Structural steel us used mostly for absorber, ductwork and supports.
Contradiction: Structured steel cannot act as a support, it is too weak. 
Contradiction: The men are settling a dispute with a game of checkers.
Contradiction: A dog is running around.
Contradiction: The kid is playing a video game
Contradiction: The man is talking