Answer:
cell membrane is the answer
Particles in solids move ever so slightly. They are not completely at rest, but since they are so packed together it’s difficult for them to move. That’s what makes a solid a solid. Particles in liquids slide and move past each other fairly quickly, and have space to move. Particles in gases are the most spread apart, and because of this, they move the quickest. Hope this helped.
The water cycle is referred to as a continuous cycle because it repeats everyday. It's a cycle with no end.