user: Question: What is the average grid that has over 8 laps, a Time/Retired of +2 Laps, and Peter Gethin driving?
Columns: ['Driver', 'Constructor', 'Laps', 'Time/Retired', 'Grid']
Types: ['text', 'text', 'real', 'text', 'real']
Sample row: ['Jo Siffert', 'BRM', 54.0, '1:30:23.91', 1.0]
SQL:

assistant: SELECT AVG("Grid") FROM "Table" WHERE "Laps" > 8.0 AND "Time/Retired" = '+2 Laps' AND "Driver" = 'Peter Gethin';