user: ### NOW ANSWER:
Question: What is the time/retired for the rider with the manufacturuer Yamaha, grod of 1 and 21 total laps?
Columns: ['Rider', 'Manufacturer', 'Laps', 'Time/Retired', 'Grid']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['Valentino Rossi', 'Yamaha', '21', '43:07.829', '1']
SQL:

assistant: SELECT "Time/Retired" FROM "Table" WHERE "Laps" = '21' AND "Manufacturer" = 'Yamaha' AND "Grid" = '1';