CREATE TABLE table_57918 ("Edition" CLOB, "Round" CLOB, "Date" CLOB, "Against" CLOB, "Surface" CLOB, "Opponent" CLOB, "Result" CLOB)

What's the date that Morocco has an Against along with a surface of hard?
SELECT "Date" FROM table_57918 WHERE "Against" = 'morocco' AND "Surface" = 'hard'
SELECT "Date" FROM "table_57918" WHERE "Against" = 'morocco' AND "Surface" = 'hard'