CREATE TABLE table_31561 ("Name" CLOB, "Circuit" CLOB, "Date" CLOB, "Winning driver" CLOB, "Winning constructor" CLOB, "Report" CLOB)

Tell me the circuit for 20 august
SELECT "Circuit" FROM table_31561 WHERE "Date" = '20 august'
SELECT "Circuit" FROM "table_31561" WHERE "Date" = '20 august'