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2. A machine is something we use to make work easier. Machines can be simple or complex:

3. A simple machine has few or no moving parts.

5. A screw A wedge A wheel and axle A lever A pulley An inclined plane 

12. inclined plane inclined surface rope wheel load

13. lever fulcrum rigid bar wheel and axle wheel axle

14. We use a hammer to knock nails into a surface

15. We use screws to fix objects together. We use a screwdriver to turn screws.

16. We use nuts and bolts to hold objects together. We use a spanner to turn bolts.

17. We use a saw to cut wood or other materials.

Machines