What do they do and what do they need ?

Detectives catch criminals. They need a dog.
Postmen deliver letters to people. They need a backpack.
Scientists learn more about plants. They need a flower.
Chefs cook food for people. They need a  pan.
Teachers teach English at school. They need a book.
Doctors look after sick people. They need an ambulance car.
Engineers design cars. They need a computer.