and but or because where - when
The fridge
What's the most useful piece of equipment in a kitchen? Is it the cooker, (1) or is it the fridge? Some people might say it's the fridge (2) and you can still cook without a cooker. You just have to light a fire. Without a fridge, it's very difficult to keep food and milk fresh. Before fridges were invented, people often used ice to keep food fresh, (3) but this as very difficult (4) because the ice melted quickly. In places (5) where there was no ice, it was very common to use salt to keep meat fresh. Do you know (6) when people first started using electric fridges? Was it 50 years ago? 100 years ago? Have a look online (7) and see if you can find out!