正规函数表是一类典型的 Tabular 表达式，被广泛应用于软件说明文档． 文中对 Tabular 表达式中正规函数表操作的语义进行研究． 首先给出了正规函数表的形式文法， 讨论了规整性、完全性和不可交叉性等性质，说明了其求值过程; 然后根据操作的影响范 围，以内部操作和外部操作为分类标准，分别对二元操作、替换操作、提取操作和扩展操作 的语义进行刻画，讨论了各个操作的封闭性;最后通过电梯控制系统实例分析了相关操作 的实际应用场景，说明了正规函数表操作的形式语义的合理性和可用性． 实例结果表明， 文中提出的正规函数表操作的语义描述与实际结果是一致的． 

As one of typical Tabular expressions，normal function table is widely used in software documents． Semantics of operators of normal function tables was studied． Firstly，the formal grammar of normal function tables was proposed． Then，regularity，completeness and disjointness were discussed and the evaluation process was explained． Next，according to the influence range of operators， the semantics of composite operator， replace operator， extract operator and expand operator were described respectively with internal operators and external operators as classification criteria，and the closure of each operator was discussed． Finally，an elevator control system example was given to illustrate the rationality and availability of formal semantics of normal function table operators． The result of the example shows that the semantic description of normal function table operators presented in this paper is consistent with the actual result．