Long Time
If you use a slide to enter a building, you'll be sliding for a long time.
Imagine a never-ending slide that goes deep down inside a building. You can't see anything in the dark around you, you just plunge down and slide forever. And forever is a long time, my friend.
きゅう, く
ひさ
None
You slide for such a long time that you get hungry. Luckily, once in a while a cucumber (きゅう) comes tumbling down the slide next to you.
Cucumbers are tasty, but not when you've been eating them for a long time.