Latin C2: Mirabile dictu: the supine & literary forms · Grammar

The supine looks like the perfect participle. In -um, after verbs of motion, it expresses purpose: venatum ire (to go hunting), cubitum ire (to go to bed). In -u, after adjectives, it means “to do”: mirabile dictu (wonderful to tell), facile factu (easy to do). Literary prose and poetry also use -ere for -erunt in the perfect (amavere = amaverunt) and the historic infinitive for vivid narration: Clamare omnes (everyone was shouting).