“所”字结构中“所”总是联系着施动者和动词,由此演变为施动关系标记,进而又虚化为焦点标记。古汉语中常见的许多“何所V”形式,其中“所”并非与V结合成“所V”结构,“所”是焦点标记,在句法层面不起作用,在语用上强调“何”。在现代汉语书面语中,还可见到古汉语遗留下来的焦点标记“所”的痕迹。 “所 ” structure “所 ” always contact the actors and verbs, which evolves into the relationship between the relationship tag, and then into the focus mark. In ancient Chinese, there are a lot of “V” forms which are commonly found in ancient Chinese, in which “” is not combined with V into “V ” structure and “” is the focus mark, In pragmatic emphasis “He ”. In modern Chinese written language, the traces of the “¡±” mark of the focus left in ancient Chinese can also be seen.