Retractable bridge

So imagine you're playing with your toy cars and you want to make a bridge for them to cross over. A retractable bridge is kind of like that, but much bigger and much cooler!

A retractable bridge is a very special kind of bridge that can move up and down or open and close like a door. Some bridges are designed this way so that boats or ships can pass through underneath without interrupting the traffic on the bridge.

Basically, the retractable bridge has big pieces at the ends that can go up or down, or back and forth to open or close the gap. This allows for boats or ships that are too big or tall to get under a regular bridge to pass through. When the boats pass, the bridge can be raised back up again so the cars can drive over it once more. It's like magic!

Retractable bridges are usually found in areas with lots of waterways or ports, where big ships come and go all the time. They are very important for making sure everything runs smoothly and nothing gets stuck or blocked.