An unremarkable shrub on the gravel plain moved and resolved into an ostrich.

砾石平原上的一株不起眼的灌木移动了一下，变成了一只鸵鸟。

Poured concrete has been the traditional material, but as more and more alternatives become available, plain concrete is yielding to ties, pavers, gravel and even tiles.

浇混凝土一直是传统材料，但随着越来越多的替代品的推出，普通混凝土的屈服关系，摊铺机，碎石，甚至瓷砖。