Abstract: The construction “Xiti X” is frequently used on the internet， and can be analyzed from three aspects： the syntactic and semantic characteristics of the components， the development and evolution of the construction， the emergence of the construction meaning， and the driving forces and mechanisms of the construction development and evolution.In terms of the structural category of “X”， the body part of the word accounts for the majority， and the fixed middle type phrases account for the vast majority. In the aspect of syllable category of “X”， there is no use case of “X” being monosyllable， and the use case of “X” being disyllable is the most. In terms of semantic categories of “X”， “X” can be divided into entity class and information class， and the information class has the semantic characteristics of ［+results In the process of construction development， the category of “X” gradually expanded， the semantic of “Ti” changed， the subject category of “Ti” gradually expanded， and the semantic of “Xi” gradually weakened. In the development process of the construction， the meaning of the construction gradually emerged.Language special district， metaphor and box filling are the motivation and mechanism of the development and evolution of the construction.