nouns, anaphors, and referential expressions. GB was the first theory to be based on the principles and parameters model of language, which also underlies the later developments of the Minimalist Program.РGB Theory (管辖与约定理论)РGovernment is defined as follows: ?A governs B if and only if? A is a governor and ? A mand B and? no barrier intervenes between A and B.РGovernment (管辖)Р其定义为: ? A是管辖语? A统治B? A和B之间无障碍РGovernors are heads of the lexical categories (V, N, A, P) and tensed I (T). A mands B if A does not dominate B and B does not dominate A and the first maximal projection of A dominates B. The maximal projection of a head X is XP. This means that for example in a structure like the following, A mands B, but B does not mand A:РGovernment (管辖)РAP? X A’? A BP? Y B? ? A mand BРGovernment (管辖)