That would depend on what you're trying to say. When talking about pre-historic history one could say something along the lines of "Since time immemorial..."
in immemorial of time i built a camp fire
in immemorial times they built stone hedges or back immemorial times they liked to listen to records.
Immemorial is an adjective.
From Time Immemorial was created in 1984.
Nile Is A River Flowing From Time Immemorial To Reach Out Generations
five
About 1066 when the domesday book was produced
i do not know how to use embalming in a sentence. (there is the sentence)
So- you are asking when to use 'when' in a sentence. When you are asking how to use when in a question, you are already using when in a sentence, because a question actually is a sentence. I like to use when in a sentence whenever I like.
How do you use sedition in a sentence
use contingency in a sentence?
use adainty as sentence