Breakdown of Post iudicium actrix iterum in scaena stat, et turba ei plaudit; laetitia in turba manet.
Questions & Answers about Post iudicium actrix iterum in scaena stat, et turba ei plaudit; laetitia in turba manet.
Post (when it means after) is a preposition that normally takes the accusative. So post iudicium uses iudicium = accusative singular of iudicium, -iī (judgment / trial / verdict).
(Compare: post + accusative is standard; unlike some prepositions, it doesn’t switch meaning by case.)
In second-declension neuter nouns, the nominative and accusative are identical in form (both singular end in -um). You identify the case from syntax: here it must be accusative because it’s the object of the preposition post.
Actrix is nominative singular feminine, meaning a female actor (actress). It’s the subject of stat.
The masculine equivalent would be actor (nom. sg.), not actorem—actorem would be accusative and wouldn’t fit as the subject here.