Rule reminder
In real texts, multiple cohesion devices work together. A paragraph may use: pronoun reference (lo/la/ci/ne), demonstrative reference (questo/tale), substitution (quello/fare lo stesso), ellipsis (omitting recoverable elements), and lexical cohesion (synonyms, superordinates). Choosing the right device depends on: (1) the gender/number of the antecedent; (2) the distance from the antecedent; (3) the register (formal/informal); (4) whether you are replacing a noun, verb, or clause.
Halliday e Hasan hanno identificato cinque categorie di coesione. ___ hanno sistematizzato per la prima volta in modo rigoroso.