astronaut [noun] someone who travels and works in a spacecraft An astronaut works in space.

businessman / businesswoman [noun] someone who works in business The businessman is trying to make a business deal.

doctor [noun] someone who helps people who are sick I went to see a doctor because I felt sick.

engineer engineer [noun] someone whose job is to design or build roads, bridges, machines etc I want to become an engineer to build roads.

fire fighter [noun] someone who stops fire from burning A fire fighter helps put out fire.

flight attendant flight attendant [noun] someone whose job is to look after or help customers on a plane The flight attendant is showing us how to use the mask.

football player [noun] someone who plays football for a living David Beckham is a football player.

plumber plumber [noun] someone whose job is to repair water pipes, baths, toilets etc We need to get a plumber to repair this water pipe.

professor [noun] a teacher who teaches at a university Professor Wong teaches mathematics at university.

secretary secretary [noun] someone who works in an office typing letters, keeping records, answering telephone calls, arranging meetings etc My secretary will fax you all the details.