No unidirectionality: Textual yào in Mandarin as contentful and procedural

Yào in Mandarin, typically a modal, has subjunctive-like uses in complement clauses. Such uses are textual in that they signal interclausal modal cohesion between the main verb and the complement clause in a construction known as the pivotal manipulative construction . They fall into three types, depending on the relationship between yào and the main verb. All three likely originate from complement clauses negated by prohibitives. However, despite a common origin, two of the types are diachronically later and more contentful, rather than procedural. Therefore, it is proposed that the development of uses in complement clauses out of modality proper does not necessarily involve unidirectional increases in procedural meaning, as is often hypothesized.