Closely focusing on the verbal domain and functional categories here proposed, the article has the following goals: further analyze the aspects of verbal morphology of Ticuna -a tonal language, genetically isolated, and spoken in the Amazon; prove how certain aspects of meaning are determined by the syntax; and determine which proposals, among those formulated for functional categories in the verbal domain, are supported by the facts of the language. The study regards certain aspectual verb suffixes in Ticuna and the expression of the causative in this language. To achieve its objectives, the article thematically outlines the theoretical course of the functional category light verb or v, considering implications and consequences in relation to the points which became part of its characterization. The conclusions which were reached reaffirm that aspects of meaning determined by the syntax exclude the external agent and indicate that, with respect to the causative, the type of complement selected by it is essential for the construction of an idiomatic expression. The study supports the verbalizing aspect of the v, the dissociation between the properties of transitivity and the semantic properties of this