【正确答案】Binding Theory regulates NP interpretation, that is to say, it assigns an appropriate interpretation to NPs at A-positions, by providing an explicit formulation of syntactic constraints on interpretation.
Binding Theory consists of three principles:
Principle A: An anaphor must be bound in its governing category;
Principle B: A pronoun must be free in its governing category;
Principle C: An r-expression must be free everywhere.
In the generative approach, binding refers to the relation between different word and the subject of a sentence containing it.

【答案解析】[解析] 本题考查约束理论概念，考生也应了解转换生成语法理论演变。