vayadhammaa sankhaaraa
decay / things / conditioned
appamaadena sampaadetha.
with zeal / strive
"[All] conditioned things decay,
Strive with zeal."
Both dhamma and sankhaara are notoriously difficult to translate.
Nanamoli has:
"It is in the nature of all formations to dissolve.
Attain perfection through diligence."