CREATE TABLE table_17733 ("Program" TEXT, "Degree" TEXT, "Focus" TEXT, "Teaching language" TEXT, "Duration  ( years ) " TEXT, "full-time/part-time" TEXT, "ECTS Credit Points" FLOAT)

What is the teaching language with the duration (years) 3.5?
SELECT "Teaching language" FROM table_17733 WHERE "Duration (years)" = '3.5'
SELECT "Teaching language" FROM "table_17733" WHERE "Duration (years)" = '3.5'