The focus of the paper is the conception of dynamic semantic scales within Firbas's theory of functional sentence perspective. In a particular context, each syntactic element performs a certain dynamic semantic function, reflecting the degree of communicative dynamism carried by the element. Each sentence implements one of three scales of dynamic semantic functions: the Presentation, the Quality, or the Combined Scale. The present paper claims that Firbas's category of the Combined Scale in reality includes two subtypes: one with ellipted Quality Bearer and Quality, and another with ellipted Phenomenon and Presentation. The paper indicates that relations within the former subtype of the Combined Scale are identical to relations within the Presentation Scale, the only difference being the presence of Specification; relations within the latter subtype are identical to relations within the Quality Scale, the only difference being the absence of the explicit introduction of the Quality Bearer in the preceding context. The paper therefore suggests a modification of Firbas's tertiary system of dynamic semantic scales into a binary system involving only the Presentation Scale, including the Extended Presentation Scale subtype containing a Specification, and the Quality Scale, including both context dependent and context independent Quality Bearers.