If something is eternal, it continues forever and without end.
- An eternal flame is a fire that never goes out. It’s kept lit in memory of someone who has died.
- A grave is an eternal resting place. It’s the place where a person is buried.
- Their love was so strong that it felt eternal, but it did not last.
- People who suffer the thousand natural shocks that flesh is heir to while here on Earth may find eternal peace in the afterlife. (from Hamlet)
- God’s love is eternal.
The word “eternally” is an adverb:
- I shall be eternally grateful if you could do this one big favor for me.
- Sarah said she was eternally grateful for the help provided to her family following the fire. (The words “eternally grateful” are often put together.)
- Inscribed on the wedding ring that Charles gave to his wife were the words “eternally yours.”
The word “eternity” is a noun that refers to a place or a time:
- It’s taking an eternity to get this project completed. (This is a good example of an exaggeration.)
- Rachel was buried next to her husband, Oscar, ensuring that they will spend all eternity together.
- I lay on the ground and contemplated eternity while looking up at the passing clouds in the sky.
Brief explanation, I was so easy to understand.
Thanks a lot Diallo