The Mayan language Mam uses complex predicates to express events. Complex predicates map multiple semantic elements onto a single word, and consequently have a blend of lexical and phrasal features. The chameleon-like nature of complex predicates provides a window on children's ability to express phrasal combinations at the one-word stage of language development. The ubiquity of complex predicates in the adult language insures that children will produce complex predicates as some of their first words. The verb complex in Mam has obligatory inflections for aspect, person, and to a degree direction. The inflections vary in degree of attachment between syllable segments, affixes, and clitics. Inflections with vowels are phonologically free, while inflections without vowels attach as either syllable segments or affixes. The Mam verb complex requires the addition of a phrasal layer to prosodic models of lexical acquisition. The paper used this extended version of prosodic theory to make five predictions for the acquisition of the verb complex. The paper analyzes production data for three children between 2;0 and 2;8 acquiring the northern variety of Mam spoken in San Ildefonso Ixtahuacán, Guatemala. The children's production data for both the intransitive and transitive verb complexes support all five predictions to some degree. The children produced prefixes more frequently on vowel-initial stems than on consonant-initial stems, and they produced imperative suffixes more frequently than prefixes on consonant-initial stems. The children exhibited developmental differences and produced phrasal contractions that the prosodic theory did not predict. The results underline the need to integrate prosody into models of morphosyntactic development, and highlight the significance of complex predicates for theories of language acquisition.