This contribution studies the behavior of the four main general light verbs (LVs) in the history of Galician (dar, facer and haber/ter). The research is structured around the following three fundamental axes: first, we study the evolution, comparison with equivalent full verbs and the morphosyntactic behavior of 26 different LV constructions (with examples that the literature identifies with different degrees of fixation) from medieval to contemporary Galician, all of which form a corpus with 8728 occurrences. Next, we discuss the results of a survey distributed to 162 respondents, which allows an assessment of these LVs from several perspectives, especially syntactic. Finally, we offer an original proposal to measure the degree of syntactic analyzability, based on the quantified review of the various parameters analyzed (of which we also provide a scale, applied synchronically and diachronically) and the results in the specific survey question. We call it Syntactic Analyzability Index (SAI) and, thanks to this index, we obtain an objective scale that projects each example on a gradation that explains the greater or lesser distance or proximity of a construction with LV from freely combined elements or from the most fixed of phrasemes.
Alexandre Rodríguez Guerra (2026) studied this question.