"jiǎ+NP" extracts from the Chinese construction "wǒ kě néng V le jiǎ N",which emerges as a network catchphrase at the beginning of 2017.The adjective "jiǎ" has a wide range of collocation,thus it has a great productivity in lexical construction.As a gradable adjective,the modifier "jiǎ" has no upper limit but lower limit in meaning.When we take something as the upper limit of "zhen(true)",then we can take as "jiǎ(false)" something else deviated from "zhen(true)".This thesis analyzes the cognitive and pragmatic interpretation of the construction "jiǎ+NP",and focuses on its features,such as diversity,vagueness and productivity within the framework of prototype theory.