Earlier constraints on movements have been reduced and simplified into a few principles with more explanation strength: Subjacency Condition, Empty Category Principle, Relativized Minimality.

• 移位是句法生成中重要的操作手段,早期一些限制移位的规则已经被简化概括成几个更有解释力的普遍原则:毗邻原则、空范畴原则、相对最简性原则。