CREATE TABLE "ships" (
  "ship" text,
  "original_pennant_number" text,
  "builder" text,
  "laid_down" text,
  "launched" text,
  "commissioned" text
);

Question: what builder launched 20 jun 1953?
SQL: SELECT "builder" FROM "ships" WHERE "launched"='20 jun 1953';

Question: what is the commissioned date with laid down of 17 dec 1951?
SQL: SELECT "commissioned" FROM "ships" WHERE "laid_down"='17 dec 1951';