Table: nfl_game_results
Columns: week
date
opponent
final_score
team_record
game_site
attendance

Question: What day were the Denver Broncos the opponent?
SQL: SELECT "date" FROM nfl_game_results WHERE "opponent" = 'Denver Broncos'

Question: What day was the oppenent the detroit lions?
SQL: SELECT "date" FROM nfl_game_results WHERE "opponent" = 'Detroit Lions'