古汉语中表示假设关系的连词“如”“若”“苟”“倘”“脱”等，用法单一意义显豁不易误训，“故”“今”“必”“当”“之”等常见虚词也可用作假设连词，其用例甚少，有时就“养在深闺人未识”，人们往往释以常见之义，似是而非未得其训。今从高中教材中撷取五例，本着“揆 In ancient Chinese, the conjunctions of hypothetical relations such as “if”, “if”, “if”, “off”, etc., use a single meaning and are not easy to be misunderstood. “Because” “this” “must” “when” “the” Common functional words can also be used as hypothetical conjunctions. There are very few use cases, and sometimes they are “keep up with people who are not well-informed.” People often give common meanings and seem to have no training. Five cases are taken from high school textbooks today, in line with