CREATE TABLE "tanker_wagons" (
  "number_name" text,
  "description" text,
  "current_status" text,
  "livery" text,
  "date" real
);

Question: Which Livery has a Description of 20t tanker, with a date later than 1941?
SQL: SELECT "livery" FROM "tanker_wagons" WHERE "description"='20t tanker' AND "date">1941;

Question: What's the Description for Scottish Tar Distillers No. 78, that's Livery is black, and a date prior to 1897?
SQL: SELECT "description" FROM "tanker_wagons" WHERE "livery"='black' AND "date"<1897 AND "number_name"='scottish tar distillers no. 78';