páng / tīng / shēng / kě / yǐ / cān / jiā / kè / táng / tǎo / lùn / dàn / bù / néng / cān / jiā / zhèng / shì / kǎo / shì

旁听生可以参加课堂讨论，但不能参加正式考试。

Auditing students may join class discussions but cannot take the formal exam.