electives

例句:

• Electives are offered in Tai Chi and advanced dance exercise.
  选修课包括太极拳和高级舞蹈练习。
  
• Students take other courses, too. These are electives.
  学生还可学习其它课程. 这些课程是选修课.
  
• The so - called electives mean only some little option within the scope of a certain item.
  所谓选修科目也只是在某一项目范围内略有拣选余地而已.
  
• She served as her class representative and took leadership classes and managerial skill electives.
  来自WSJ
• While the curriculum focuses on math and science, there's a heavy dose of liberal arts, electives and foreign language study.
  来自VOA