CREATE TABLE "classification" (
  "driver" text,
  "constructor" text,
  "laps" real,
  "time_retired" text,
  "grid" real
);

Question: Who constructed the car that has a Time/Retired of engine, and over 50 laps?
SQL: SELECT "constructor" FROM "classification" WHERE "time_retired"='engine' AND "laps">50;

Question: What is the time/retired for ronnie peterson with under 75 laps and a grid under 15?
SQL: SELECT "time_retired" FROM "classification" WHERE "laps"<75 AND "grid"<15 AND "driver"='ronnie peterson';