user: Question: On what date was the Opponent Chicago Bears?
Columns: ['Week', 'Date', 'Opponent', 'Result', 'Record', 'Attendance']
Types: ['real', 'text', 'text', 'text', 'text', 'text']
Sample row: [1.0, 'September 1, 1991', 'Seattle Seahawks', 'W 27-24', '1-0', '68,492']
SQL:

assistant: SELECT "Date" FROM "Table" WHERE "Opponent" = 'Chicago Bears';