How are cars made?
Making a car used to take a very long time. In the early 1900s, mass production changed everything: cars were made on assembly lines. The car moved along a belt and each worker added some parts at their station. Henry Ford's factory made the Model T this way, quickly and cheaply.
A modern car factory
- 1🔩 Parts are made
Each car is made of thousands of smaller parts.
- 2🤖 Robots assemble the car
Powerful robots, controlled by computers, weld the body parts together.
- 3🧑🔧 Workers finish the job
People check the car and finish some jobs by hand.
- 4🚚 The cars leave the factory
They travel by road, rail or sea to the shops.
When the important thing is the action, not who does it, we use is/are + past participle: Cars are made in factories. The robots are controlled by computers.
Use the past continuous for an action that was happening when something else happened: Röntgen was experimenting when he discovered X-rays. Edison was tryingto make a light bulb for years.