Explanation:

 · In desert landforms, when wind blows, it lifts and transports sand form one place to another. When it stops blowing the sand falls and get deposited in low hill like structures these are called sand dunes.
· When the grains of sand are very fine and light, the wind can carry it over very long distances. When such sand is deposited in large areas it is called loess. Large deposits of loess is found in China.