这看似是由白色材料绘制而成的宽线。
象牙是一种很难找的白色材料，它们来自象的两个长牙。
Ivory is the hard white material that forms an elephant's two long teeth, or tusks.
这看似是由白色材料绘制而成的宽线。或者，也许是由机器挖掘过的土地。
They seem to be wide lines drawn with some white material. Or maybe the dust have been dug by machinery.
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