printer

Everyday

1. A printer is a machine that prints words and pictures on paper from a computer. tree →
2. A printer is also a person or company whose job is printing books, newspapers or posters. tree →
3. A 3D printer builds solid objects layer by layer. tree →

In the lessons

In school maths: a machine printing pages at a rate (pages per minute); time = pages ÷ rate; two printers working together add their rates; sheets of paper in the tray. In everyday life: printing homework, out of ink, a paper jam. In history: the printing press made books cheap. Phrases: «printer ink», «paper jam», «3D printer», «laser printer».

Examples

• A printer prints 15 pages a minute. tree →
• Two printers work together. tree →
• The printer has 200 sheets. tree →
• How long to print 90 pages? tree →
• The printer has run out of ink. tree →
• There's a paper jam in the printer again. tree →
• Our school 3D printer made a plastic dinosaur. tree →
• Send the photo to the printer. tree →

Note

Countable: «a printer». Maths: a rate: time = pages ÷ rate. Trap: two printers together add their rates (15 + 15 = 30 pages a minute), so the time halves.