How do the states of matter relate to the water cycle?
Well, what happens to a bowl of water, when you leave it outside on a summer's day?
If evaporates....i.e. it undergoes the phase transition...
And it joins with atmospheric moisture in the form of clouds or humidity...
And under some circumstances, the water precipitates back down as liquid water as rain...to ruin your afternoon...and the rain collects in creeks and rivers, and eventually drains out to the sea.
And in the polar regions, the liquid water undergoes fusion to give ice...that ice, solid water, is less than liquid water, and thus floats on liquid water is an highly unusual and characteristic property of water.