Abstract:The paper consists of four parts.The first part argues from the perspectives of fact and theory that though useful, construction theory does not explain everything.The second part tries to explain the generation of constructions from the perspectives of external language and internal language.From the perspective of external language, language variation is a common phenomenon.Linguistic variations generalize after frequent use and become new grammatical constructions.From the perspective of internal language, construction originates from cognition, which can be approached with two hypotheses:"internal to external mechanism" and "external to internal mechanism".The third part uses examples to argue that in order to play a better role, construction theory needs to be combined with chunk theory.The fourth part proposes a question for further study:What kind of relationship should construction and linguistic information structure have?