Answer: Rock is broken by different kinds of erosion
Explanation: Erosion in many kinds can break down rocks; Ice can break it by penetrating as water into cracks, and when it freezes, it expands and breaks the rock. Wind can also erode rock over a long period of time, however it doesn't really break solid rock; it forms dunes out of sand instead. Water in rivers or lakes can also break it with current. And finally, plant roots can penetrate through gaps and grow thicker inside, breaking the rock with pressure.
