中文摘要：

疑问句和假设句是人类语言普遍存在的句子类型。疑问和假设作为最重要的非线性成分在句法上表现为作用于全句的语用特征，这些特征必须通过添加标记、移位、重叠等有限的句法操作影响甸子的线性结构在句子表层得到体现，从而形成疑问句、假设句。当句子同时包含特指疑问词和假设特征时，特指疑问词所包含的词汇疑问特征将会被抑制，句法上表现为特指疑问词在假设句中的任指和虚指用法，这一现象可以通过疑问特征和假设特征的实例化推导出来。

英文摘要：

Interrogation and hypothesis, as the most important pragmatic functions in human language, are syntactically embodied as the sentence--wide pragmatic features. These features must be reflected in the surface level of sentences through some limited syntactic operations such as tags- addition, shift, reduplication and so on, which can influence the linear structure of the sentence, and thus interrogative and hypothetical sentences are formed. When both an interrogative wh--word and a hypothetical feature are contained in the same sentence, the interrogative feature carried in the interrogative wh--word will be suppressed. As a result, the interrogative wh- word syntactically will display non- referential and arbitrary referential usages in a hypothetical sentence. This phenomenon can be deduced by the instantialization of interrogative and hypothetical features.