Xiangdangran(想当然)first appeared in the Southern Song Dynasty,but during the Ming and Qing dynasties,its semantics and usage underwent changes due to changes in usage scenarios,which promoted and influenced the emergence and usage of the fixed structure xiangdangran(想当然)in modem Chinese.In its own evolution,xiangdangran()is accompanied by a process of delexicalization,primarily manifested in its gradual shift from a post-predicate position to a pre-adverbial position.It has also exhibited cases where it can be understood as a conjunctive adverb.These stages are evident in its grammaticalization process.Although xiangdangran(想当然)is often used as a fixed structure in modern Chinese,it has not yet fully solidified into a single word and is only in the initial stage of lexicalization-idiomatic.