CREATE TABLE "winners_knockout" (
  "home_1st_leg" text,
  "home_2nd_leg" text,
  "1st_leg" text,
  "2nd_leg" text,
  "aggregate" text
);

Question: What was the 2nd leg score having an aggregate score of 4-2?
SQL: SELECT "2nd_leg" FROM "winners_knockout" WHERE "aggregate"='4-2';

Question: What was the home team for the 2nd leg for the match having a 1st leg score of 2-1?
SQL: SELECT "home_2nd_leg" FROM "winners_knockout" WHERE "1st_leg"='2-1';

Question: What was the home team for the 2nd leg of the match having an aggregate of 2-3?
SQL: SELECT "home_2nd_leg" FROM "winners_knockout" WHERE "aggregate"='2-3';