switch

Everyday

1. A switch is a small button or lever that turns a light or a machine on or off. tree →
2. To switch is to change one thing for another, or to swap. tree →
3. To switch on or switch off is to start or stop a light or machine. tree →
4. A switch is a sudden change, like a switch from rain to sun. tree →
5. A switch is also a thin, bendy stick or twig, and to switch someone is to hit them with one. tree →

In the lessons

switches on a wall are counted; to switch is to change places or to swap things, so amounts move between people; in everyday life and safety: switch off lights to save energy, never touch a switch with wet hands; in science a switch opens or closes an electric circuit; phrases: «switch on», «switch off», «switch places», «switch sides»

Examples

• Each room has 2 light switches. tree →
• They switch seats. tree →
• Tom switches 3 of his cards for 3 of Ben's. tree →
• She switches the lamp off. tree →
• Please switch off the lights when you leave the room. tree →
• In the circuit, the bulb lights up when the switch is closed. tree →
• The team switched sides at half-time. tree →
• Dry your hands before you touch a switch. tree →
• He switched from football to swimming this year. tree →
• Aboo!” and at the same time he switched the naked baby with a thorny wild-rose bush. tree →

Note

A swap of equal numbers keeps each total the same. Trap: switching places changes positions, not how many. Plural: switches. In science: a closed switch lets the current flow (bulb on); an open switch stops it. «Switch on/off» = «turn on/off».