en_tn/mrk/15/21.md

they forced him to carry his cross

According to Roman law, a solider could force a man he came upon along the road to carry a load. In this case, they forced Simon to carry Jesus' cross.

from the country

"from outside the city"

A certain man, ... Rufus), and

This is background information about the man whom the soldiers forced to carry Jesus' cross. (See: rc://en/ta/man/translate/writing-background)

Simon ... Alexander ... Rufus

These are names of men. (See: rc://en/ta/man/translate/translate-names)

Cyrene

This is the name of a place. (See: rc://en/ta/man/translate/translate-names)