Friendly Ork turn:
4 of the friendly orks just move around, all set to take out the Guardsmen next turn if need be.
1 of the slugga boyz charges the last remaining guardsman.
He has two melee attacks from his slugga. One at 3+ because of the +1 modifier for charging and +1 for additional combatant, and the remaining one at 5+.
You blow on two 6-sided dice, and throw:
First die lands...
You rolled a 1.
Second die lands...
You rolled a 5.
The remaining guardsman in that sector is struck down by the slugga boy.