Table: formula_one_1969
Columns: constructor
chassis
engine
tyre
driver
rounds

Question: Which rounds did Vic Elford with a Ford cosworth dfv 3.0 v8 engine have?
SQL: SELECT "rounds" FROM formula_one_1969 WHERE "driver" = 'vic elford' AND "engine" = 'ford cosworth dfv 3.0 v8'

Question: What is the chassis for Bruce Mclaren with all rounds and a g tyre?
SQL: SELECT "chassis" FROM formula_one_1969 WHERE "rounds" = 'all' AND "tyre" = 'g' AND "driver" = 'bruce mclaren'