Anchor: This may be the last chance to reverse the process."  
Entailed: If this chance is not taken, the process might be irreversible.
Contradiction: There will definitely be more chances to reverse the process.
Contradiction: Oh, many homeowners around here keep their homes cool all year around.
Contradiction: An older person is sweeping.
Contradiction: She left it upstairs when she came down.
Contradiction: Separate guided tours are necessary to visit several parts of the chateau.