Table: italian_grand_prix_1999
Columns: driver
constructor
laps
time_retired
grid

Question: When the laps are over 53, what's the average grid?
SQL: SELECT AVG("grid") FROM italian_grand_prix_1999 WHERE "laps" > 53

Question: What's the average laps driven by david coulthard?
SQL: SELECT AVG("laps") FROM italian_grand_prix_1999 WHERE "driver" = 'david coulthard'