A: Mr Sellers, it's Steven speaking, your tenant. We've just suffered a power failure. What should I do now?
B: Alright, Steven. Do you have a flashlight?
A: Yes, I do.
B: Okay, now go down to the basement and find the circuit box. Open it and check if there are any fuses blown out.
A: How do I know if it's blown out?
B: You'll see it's black and has burned smell.
A: Then what should I do?
B: Unscrew the burnt fuses and replace them with the good ones. You can find them on the rack in the basement.
A: Okay, I'll try. I'll call you if it doesn't work.
The power just went out/off.
The power is out/off
The electricity is gone/out/off.
We are having a blackout.
We had a power outage for about half an hour.
The fuse has blown out.
（to undo sth by twisting or turning it）
Can you help me unscrew the lid of this jar?
You have to unscrew all the screws.
God help us if it doesn't work.
The pump doesn't work and we have no running water.
My washing machine doesn't work.