Well, when you're off to work, under the road or under the buildings that you see, there might very well be cellular concrete, which is a very light kind of concrete that's actually got proteins from bones inside and it's also fully reusable.
当你下了班，你看到的路面底下，或建筑物下面， 很可能铺有微孔混凝土， 这种混凝土很轻， 其中就有从猪骨头中获取的蛋白质。 它还能被重复利用。