This chapter discusses 4 case studies: (1) manner adverbs, which form a syncretic category with adjectives but, syntactically, form a class apart in showing agreement patterns tied to specific types of alignment, challenging the view that adverbs never show agreement; (2) finiteness is traditionally assumed to be a binary opposition, yet southern dialects reveal a more fine-grained distribution with hybrid categories such as inflected infinitives, and with some dialects extending inflectional agreement to all parts speech, causing us to rethink traditional criteria for establishing word classes; (3) vocatives represent an understudied class that are formally marked off as a separate category in southern Italy, but which formally and functionally share and blend numerous properties of various word classes; (4) finite markers of subordination in southern Italy variously distinguish between realis, irrealis and factive modality, forcing us to question the existence of a single, homogeneous class of complementisers across Romance and to recognize that irrealis markers may belong to a distinct class of subordinating elements variously distributed across the C- and I-spaces.