So I'm the most efficient brick producer if I can make the cheapest brick. 假如我能够生产成本最低的砖,我就是最有效率的制砖工人。
The professor has developed a method of transferring sludge into innoxious materials for bricks and cement at a low cost. 这名专家找到的办法可以以较低的成本把淤泥变成无害的材料用来制砖和水泥。