what is the competing entities when the age group is 18 or younger, held every is one year and the sport is table tennis?
CREATE TABLE "women" (
  "sport" text,
  "competition_name" text,
  "competing_entities" text,
  "age_groups" text,
  "held_every" text
);
SELECT "competing_entities" FROM "women" WHERE "age_groups"='18 or younger' AND "held_every"='one year' AND "sport"='table tennis';