retractable

例句：

1. 1. The car's brakes are retractable, allowing you to stop quickly.
   这辆车的刹车是可伸缩的，可以让你快速停下来。
2. 2. The tent is retractable, so it can be folded up easily.
   这个帐篷是可伸缩的，所以可以很容易地折叠起来。
3. 3.The zipper on the suitcase is retractable, which makes it easy to open and close.
   行李箱上的拉链是可伸缩的，这使得打开和关闭变得容易。