en_tn/gen/15/12.md

Abram fell sound asleep

"A deep sleep fell on Abram."

fell sound asleep

"fell into a very deep sleep" or "slept deeply." It means that he was very much asleep.

deep and terrifying darkness

"extreme darkness that that terrified him"

overwhelmed him

"surrounded him"

strangers

"aliens" or "foreigners"

and will be enslaved and oppressed

This can also be translated with an active clause: "and the owners of that land will enslave your descendants and oppress them." (See: rc://en/ta/man/translate/figs-activepassive)