CREATE TABLE nomination (artwork_id NUMBER, festival_id NUMBER, result CLOB)
CREATE TABLE festival_detail (festival_id NUMBER, festival_name CLOB, chair_name CLOB, location CLOB, year NUMBER, num_of_audience NUMBER)
CREATE TABLE artwork (artwork_id NUMBER, type CLOB, name CLOB)

Show distinct types of artworks that are nominated in festivals in 2007.
SELECT DISTINCT T2.type FROM nomination AS T1 JOIN artwork AS T2 ON T1.artwork_id = T2.artwork_id JOIN festival_detail AS T3 ON T1.festival_id = T3.festival_id WHERE T3.year = 2007
SELECT DISTINCT "T2"."type" FROM "nomination" "T1" JOIN "artwork" "T2" ON "T1"."artwork_id" = "T2"."artwork_id" JOIN "festival_detail" "T3" ON "T1"."festival_id" = "T3"."festival_id" AND "T3"."year" = 2007