Course[] course2 = {new Course("6","計算機網絡"),new Course("7","單片機原理")};

coursesToSelect.add(2, Arrays.asList(course2));

Course temp6 = (Course)coursesToSelect.get(2);

Course temp7 = (Course)coursesToSelect.get(3);

System.out.println("又添加了兩門課程：" + temp6.getId() + ":" +?

temp6.getName() + "\n" + temp7.getId() + ":" + temp7.getName());