CREATE TABLE "reformations_and_conversions" (
  "units" text,
  "type" text,
  "period_used" text,
  "formed_from" text,
  "trailers" text
);

Question: Name the trailers for formed from pan/pul/res cars
SQL: SELECT "trailers" FROM "reformations_and_conversions" WHERE "formed_from"='pan/pul/res cars';

Question: Name the typed for formed from 6-pul trailer third in res unit
SQL: SELECT "type" FROM "reformations_and_conversions" WHERE "formed_from"='6-pul trailer third in res unit';

Question: Name the formed that has type of 4-cor
SQL: SELECT "formed_from" FROM "reformations_and_conversions" WHERE "type"='4-cor';