CREATE TABLE table_39056 ("Outcome" CLOB, "Date" CLOB, "Tournament" CLOB, "Surface" CLOB, "Partner" CLOB, "Opponent" CLOB, "Score" CLOB)

What person was played against when the playing surface was hard?
SELECT "Opponent" FROM table_39056 WHERE "Surface" = 'hard'
SELECT "Opponent" FROM "table_39056" WHERE "Surface" = 'hard'