Read the article titled "Coastlines: Works in Progress." Using two or three sentences, describe the role of waves in shaping Earth's coastlines. (Site 1)

Answer: Waves through their nonstop action play a role in shaping the earth's coastline. This they achieve by their constant ability to move sands and gravel, breach barriers, build walls and even sculpt bays. As a result, no coastline ever remains the same for long.

Explanation: Coastlines are lines where land meets water. They constantly are changed and reshaped by waves built up by winds far out at sea, which unleash their energy when they break on the shore. They deliver sand and gravel to, move them along and also out of the beach.

This nonstop action means nothing ever stays the same. Breakers gnaw away at cliffs, shift sand to and fro, breach barriers, build walls, sculpt bays etc.