CREATE TABLE people (Hometown VARCHAR2, People_ID VARCHAR2)
CREATE TABLE gymnast (Gymnast_ID VARCHAR2)

What are the hometowns that are shared by at least two gymnasts?
SELECT T2.Hometown FROM gymnast AS T1 JOIN people AS T2 ON T1.Gymnast_ID = T2.People_ID GROUP BY T2.Hometown HAVING COUNT(*) >= 2
SELECT "T2"."Hometown" FROM "gymnast" "T1" JOIN "people" "T2" ON "T1"."Gymnast_ID" = "T2"."People_ID" GROUP BY "T2"."Hometown" HAVING COUNT(*) >= 2