CREATE TABLE table_2721 ("Team" TEXT, "Outgoing manager" TEXT, "Manner of departure" TEXT, "Date of vacancy" TEXT, "Replaced by" TEXT, "Date of appointment" TEXT)

Name the manner of departure for 1 december 2009
SELECT "Manner of departure" FROM table_2721 WHERE "Date of vacancy" = '1 December 2009'
SELECT "Manner of departure" FROM "table_2721" WHERE "Date of vacancy" = '1 December 2009'