en_tn/est/04/01.md

learned of all that had been done

"found out about those letters"

tore his clothes and put on sackcloth and ashes

These acts are signs of severe sadness. AT: "tore his clothes and put on sackcloth and ashes to show his grief" (See: rc://en/ta/man/translate/translate-symaction)

province

A "province" is a large area into which some countries are divided for the purposes of government. See how you translated this in Esther 1:1.

there was great mourning among the Jews

"the Jews mourned greatly"

Many of them lay in sackcloth and ashes

"Many of them were on the ground, dressed in sackcloth and sitting in ashes"