copper

Everyday

1. Copper is a reddish-brown metal that conducts electricity and heat very well. tree →
2. Copper is also a reddish-brown colour. tree →
3. Coppers are small brown coins (UK). tree →
4. A copper is an informal British word for a police officer. tree →
5. A copper can also be a large metal pot, used for heating water or brewing. tree →

In the lessons

In science lessons copper is used for electric wires because it is a good conductor; it turns green when it reacts with air over many years (like the Statue of Liberty). Phrases: «copper wire», «copper pipes», «copper coins».

Examples

• Electric wires are often made of copper. tree →
• The Statue of Liberty is green because its copper changed over time. tree →
• She has copper-coloured hair. tree →
• Copper is a good conductor of heat. tree →
• Old pennies are made of copper. tree →
• Copper pipes carry water in the house. tree →
• The copper caught the thief (old British slang). tree →
• The wood flamed up splendidly under the large brewing copper, and it sighed so deeply! tree →

Note

Uncountable as a metal. Its chemical symbol is Cu. The green coating is called verdigris or patina; it is not rust (only iron rusts). Never touch exposed copper wires; electricity is dangerous.