短語詞組短語Optional courseelective course 選修課optional soccer course 足球選項課optional volleyball course 排球普修課optional l course 選修課;選修課程public optional experiment course 實驗公選課Optional Main Course 主食optional sport course 選項運動課程Optional Elective Course 任意選修課generally optional gymnastics course 體操普修課 返回 optional course