CREATE TABLE "previous_winners" (
  "year" real,
  "mens_singles" text,
  "womens_singles" text,
  "mens_doubles" text,
  "womens_doubles" text,
  "mixed_doubles" text
);

Question: Who won the womens singles event the year that Jonas Lyduch won?
SQL: SELECT "womens_singles" FROM "previous_winners" WHERE "mens_singles"='Jonas Lyduch';

Question: Who won the mens doubles the year Alison Humby won the womens singles?
SQL: SELECT "mens_doubles" FROM "previous_winners" WHERE "womens_singles"='Alison Humby';