A contextual grammar is a language generating mechanism inspired by generating sentences in natural languages. An existing string can be extended to a new string of the language by adjoining a context before and behind the string or by inserting it into the string around some subword. The first mode is called external derivation whereas the second mode is called internal derivation. If conditions are given, around which words which contexts can be adjoined, we speak about contextual grammars with selection. We give an overview about the generative capacity of contextual grammars (working externally or internally) where the selection languages belong to subregular language classes. All languages generated by contextual grammars where all selection languages are elements of a certain subregular language family form again a language family. We compare such families which are based on finite, monoidal, nilpotent, combinational, definite, suffix-closed, ordered, commutative, circular, non-counting, power-separating, or union-free languages, or based on languages defined by restrictions regarding the descriptional complexity.

中文翻译：

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次规则选择语言的上下文语法的生成能力

上下文语法是一种语言生成机制，其灵感来自于以自然语言生成句子。通过在字符串前后添加上下文，或将其插入到某个子词周围的字符串中，可以将现有字符串扩展为该语言的新字符串。第一种模式称为外部派生，而第二种模式称为内部派生。如果给定条件，可以围绕哪些词衔接哪些上下文，我们将讨论带有选择的上下文语法。我们概述了上下文语法（在外部或内部工作）的生成能力，其中选择语言属于次常规语言类。由上下文语法生成的所有语言（其中所有选择语言都是某个次正规语言族的元素）再次构成了一个语言族。