2. SOME THINGS ABOUT SCREWS
The ancient people made screws to make work easier.
Screws can be reversed
Screws are a helpful tools.
3. DEFINITION OF SCREWS
A screw is a metal object similar to nail, with a spiral ridge around it
which is used to attach one thing to another.
4. DIFFERENT SCREWS
A screw is made of lots of inclined planes.
Some stairs are shaped like screws.
When you clean a gun you need something long
so you screw poles together.
Some slides are shaped like screws.
When you turn a screw the pieces come together.
Did you now the screw is one of six simple
machines that have been around since ancient
times.