先秦汉语中无动作性“为”字到底是动词还是系词，这是个至今仍无定论的问题。本文在前人研究的基础上，就“Ｓ为Ｏ（ＮＰ）”句式中无动作性“为”字，对先秦具有代表性的十三部文献作了穷尽式的调查，进而从多个角度对这类“为”字作了描写和讨论，由此得出了以下主要结论：一是这类“为”已初步具备了系词的性质，但还不成熟，是个准系词；二是准系词“为”字句的分布与无系词判断句存在互补性。同时，本文也对“系词说”和“非系词说”的某些观点提出了不同的看法 In Pre-Qin Chinese no action “for” in the end is a verb or co-word, which is still a question of uncertainty. On the basis of the previous studies, this paper makes an exhaustive investigation on the thirteen documents that are representative of the pre-Qin period, on the basis of the non-action “bei” in the sentence “S is O (NP) From the perspective of this type of ”for“ the words were described and discussed, which led to the following main conclusions: First, these ”as“ has the preliminary nature of the word, but not yet mature, is a quasi-word; Is a quasi-word ”for“ the distribution of sentences and non-co-existence of sentence judgments complementarity. At the same time, this article also put forward some different opinions on some of the views of ”co-word“ and ”non-co-word"