Verb aspect, alternations and quantification In this paper we are briefly discuss the nature of Bulgarian verb aspect and argue that the verb aspect pairs are different lexical units with different (although related) meaning, different argument structure (reflecting categories, explicitness and referential status of arguments) and different sets of semantic and syntactic alternations. The verb prefixes resulting in perfective verbs derivation in some cases can be interpreted as lexical quantifiers as well. Thus the Bulgarian verb aspect is related (in different way) both with the potential for the generation of alternations and with the prefixal lexical quantification. It is shown that the scope of the lexical quantification by means of verbal prefixes is the quantified verb phrase and the scope remains constant in all derived alternations. The paper concerns the basic issues of these complex problems, while the detailed description of the conditions satisfying particular alternation or particular lexical quantification are subject of a more detailed study.