Thunder roared, and lightning ran.

He is an expert in electronics.

Molybdenum is an important element in the production of steel.

Electromagnetism is a part of physics that studies the interaction between electricity and magnetism.

I commute by train every day.

This computer is using the latest technology.

We installed solar batteries on the roof of our house.

He sent me important information by telegram.

The battery ran out, and the light stopped working.

The incandescent light bulb has burned out, so I'm going to buy a new one.