CREATE TABLE table_204_628 (id NUMBER, "trial number" CLOB, "date" CLOB, "name of trial" CLOB, "celebrity/ies taking part" CLOB, "winner/number of stars" CLOB, "notes" CLOB)

jan and scott took part in trial number 10 . who took part in the previous trial ?
SELECT "celebrity/ies taking part" FROM table_204_628 WHERE "trial number" = 10 - 1
SELECT "celebrity/ies taking part" FROM "table_204_628" WHERE "trial number" = 9