Complex collocations are a type of collocation whose syntactic structure is more complex than that of simple collocations. Thus, they are binary standardized or frequent phrases whose components show a lexical restriction relationship. The complex character of its structure means that
one of its components, the collocative, is not a lexical unit, but rather a fixed phrase. Most of them are adverbial, either in the case of verbal predicates (llover a cántaros) or adjectival predicates (loco de atar), although they can also — in less frequent cases
— be adjectival, as when combined with a noun (dinero en efectivo), or also nominal, in combination with a verb (hacer un corte de mangas).