The stars emit radiation which can be detected by special instruments.

The universe is getting bigger by miles and miles every second.

The speed of light is the fastest possible speed.

There are things in space called black holes, where no light can escape.

selling things to passengers in a shop he set up in a train carriage

taking photographs of people in the street, charging a penny per photo

working for a failed inventor who once was a family friend

travelling around the country, playing music with an early phonograph

She invented a gadget that turned seawater into drinking water.

She created a way to direct solar power to field hospitals.

She developed a reusable bandage for their wounds.

She produced a thicker kind of metal to be used in their helmets.

He created the first-ever website.

He built the world's first Bluetooth device.

He developed a chatbot that talked to users.

He invented the first mobile phone.

The sugar grown in India was not sweet enough due to hot weather.

The Indian sugar plants had become diseased, and would not go to seed.

The snails in India had begun eating all the sugar plants.

She was trying to create a potato that could survive in sandy soil.