The diagrams explain the processes of producing cement and concrete. Overall, there are five stages for making the cement and one for the concrete. The cement must (1. to make) first, as it (2. to use) to make the concrete. To make cement, firstly limestone and clay (3. to feed) into two rollers which (4. to crush) them up into a powder. This power (5. to mix + then) together, before (6. to travel) down a tube and into a rotating heater. The heat comes up from the bottom as the heater rotates, and once the power is ready, it (7. to emerge) from this machine onto a conveyor belt where it (8. to grind + then) into the cement. Finally it (9. to separate) into bags. This cement is then used to produce the concrete. To do this, there is a mixture of 15 per cent cement, 10 per cent water, 25 per cent sand and 50 per cent gravel. These (10. to place) into a concrete mixer, which spins in order to form the concrete.