zài / zhé / xué / kè / shàng / lǎo / shī / jiè / shào / le / yī / yuán / lùn / hé / duō / yuán / lùn / de / qū / bié在哲学课上,老师介绍了一元论和多元论的区别。In philosophy class, the teacher explained the difference between monism and pluralism.