Preposition: of

• time: There has been fighting in the Middle East for eons of time.

• history: The rocks of both sharing in common the eons of history that have passed since their birthing.

Converse of object

• take: Fossils, coal deposits, petroleum deposits, all of them took immense eons to form.

• seem: It seemed eons since she and Alex had sat for hours at dinner and chatted about the things that were important to them.

• wait: It was captured by Saturn's gravitational field and has been waiting eons for Cassini to come along.

• start: What happened to the dandelions, violets, thistle and stuff I started eons ago?

Adjective modifier

• Proterozoic: Symbiosis in Cell Evolution: Microbial Communities in the Archean and Proterozoic Eons, second edition.

• Hadean: Earth condenses from the hot gases of the Solar Nebula... January to early March: Hadean eon.