on the moon's cycles, but the lunar calendar failed to predict a critical event in their lives: the annual flooding of the Nile river.
(the lunar calendar; failed; to predict a critical event in their lives; T:on the moon's cycles) (the lunar calendar; to predict; a critical event in their lives)
the lunar calendar the lunar calendar
failed to predict
to predict a critical event in their lives T:on the moon's cycles
a critical event in their lives