体词谓语句为何加“是”

Why Add Shi(是) to the Sentence with Nominal Predicate

体词谓语句中加'是'是语用的需要,'是'的语用功能是表示发话人对主语体词、谓语体词之间陈述关系的肯定。当主语体词与谓语体词之间是等同关系时,两个体词之间的概念距离远,其间的陈述关系不容易被受话人理解,谓语体词前需要加'是',否则句子要借助特殊的语境条件才能成立;主语体词与谓语体词之间是归属关系时,两个体词之间的概念距离有近有远,谓语体词前是否加'是'要视主语体词与谓语体词之间概念距离的远近而定。

In modern Chinese when the verb shi(是) is used with a nominal predicate, it has a pragmatic function to affirm the semantic re-lation between the subject and the predicate. When the subject nominal and the predicate are in an equative relation, they are conceptually distant, and it can be difficult for the hearer to identify the semantic relationship in between. This is when shi can be added before the predicate to specify the relationship. When the subject and the nominal predicate are in an inclusive relation, the two entities are not always conceptually distant, so one has to examine the conceptual distance between them to figure out whether shi should be added.