Towards the end of the 20th century, several linguistic theories were introduced into China from the West. Most notable among these was Chomsky’s Generative GrammarGenerative Grammar. Generative Grammar proposes that human beings are biologically endowed with a Universal Grammar (UG) consisting of a set of invariant underlying principles that apply to all languages and a set of parameters (e.g., Head Directionality Parameter, Pro-Drop Parameter) that can be ‘set’ on a language-by-language basis. That is, grammatical principles that are assumed to be in operation in one language must be in operation in all other languages, but each language may have its parameters ‘set’ differently.