It is traditionally assumed that the lexical semantic information of verbs specifies the number of arguments and argument structure in generative grammar. However, argument structure alternation, which reveals the fact that certain verbs may appear in different subcategorization frames while maintaining the core meanings, casts doubts on this assumption. Based on the facts coming from causative alternation, ditransitive alternation and locative alternation, this paper addresses the influences of argument alternation on the understanding of argument licensing, and it summarizes that verbal classification according to lexical semantic information was generally applied to the issue of argument structure alternation in previous research. This paper furthermore proposes that if the syntactic realization of arguments simply reflects the direct lexical information of verbs, then argument realization should be restricted to few syntactic representations, which is not in accordance with facts. Therefore, it becomes a central issue to explore for the study of argument licensing that to what extent the syntactic realizations of arguments contain lexical semantic information.