CREATE TABLE "series_3" (
  "series_sorted" text,
  "title" text,
  "doctor" text,
  "featuring" text,
  "released" text
);

Question: what is the released when the series is sorted 6y/ai?
SQL: SELECT "released" FROM "series_3" WHERE "series_sorted"='6y/ai';

Question: who is the featuring when the doctor is the 6th and the series sorted is 6y/ak?
SQL: SELECT "featuring" FROM "series_3" WHERE "doctor"='6th' AND "series_sorted"='6y/ak';

Question: what is the series sorted when the released is may 2012?
SQL: SELECT "series_sorted" FROM "series_3" WHERE "released"='may 2012';

Question: who is the featuring when the series sorted is 6eb/b?
SQL: SELECT "featuring" FROM "series_3" WHERE "series_sorted"='6eb/b';