“旁听生”的英语？

鸿 渐 明天上课, 那三个旁听生不来了.The next day when Hung - chien it went to class, the three auditors were not there.也鼓励相关专题的旁听生在最后一节课中展示他们的作品.Auditors working on related projects are also encouraged to present their work during these...