According to Zhu Dexi (1984) the difference between the two word classes: substantive and predicate, is that a substantive cannot serve as a predicate in a sentence but a predicate can.

• 摘要区分体词和谓词的出发点是只有谓词可以充当谓话，而体词不能这样做（朱德熙1984），体词谓语句因而是个自相矛盾的概念。