I need to spend hours studying this weekend for my exams; ergo, I will not be attending the game.
I left the meeting a few minutes early; ergo, I don't know what the plans are for the next event.
There's a high pollen count today, ergo, I will not be going outside because my seasonal allergies have flared up.
My electric bill is way too high; ergo, I will stop leaving the lights on when I am not in the room.
Eva wanted to stay away from her family for a few hours; ergo, she went out for dinner with friends.