Hence (adverb)
from here, from this place, away
“I’m going hence, because you have insulted me.”
“Get thee hence, Satan!”
Hence (adverb)
from the living or from this world
“After a long battle, my poor daughter was taken hence.”
Hence (adverb)
in the future from now
“A year hence it will be forgotten.”
Hence (adverb)
as a result; therefore, for this reason
“I shall go to Japan and hence will not be here in time for the party.”
“The purse is handmade and hence very expensive.”
Hence (interjection)
Go away! Begone!
“”…Hence! and bestow your dead”
“Where no wrong against him cries!””
Since (adverb)
From a specified time in the past.
“I met him last year, but haven’t seen him since.”
Since (preposition)
From: referring to a period of time ending in the present and defining it by the point in time at which it started, or the period in which its starting point occurred.
Since (preposition)
Continuously during that period of time.
“I have known her since last year.”