IELTS Writing Task 1
The diagrams below show how sand dunes are formed.
Sample Band 7.0+
The diagrams illustrate the formation of sand dunes from sand particles.
Overall, there are three stages, beginning with sand particles being blown by the wind and ending with them stacking on top of each other to make sand dunes. Besides, four elements are involved in this natural phenomenon, including sand particles, wind, wet ground, and dry ground.
To commence, sand particles scattered all over the ground are driven by wind. Specifically, the wind blows downward to carry them from dry ground to wet ground, which contains water to increase the adhesion. As this process continues, particles of sand start to pile up on top of each other.
Once formed to a certain height, the sand dune creates a blockage, deflecting the wind upward on one side and forcing it downward on the other. This results in sand particles on the top of the dunes rolling downhill to other nearby wet grounds and forming other hills of sand.
157 words
