The pair spent much of the race trading places, often a number of times per lap. 他俩在比赛的大部分时间都胶着在一起,基本上每圈都因此多花了一些时间。
Demand for cement is growing faster than emissions per tonne are falling, leading to an overall increase in emissions. 一个多世纪以来,水泥生产商们一直致力于提高煤窑的燃烧效率,因此能够大幅提高的空间相对来说不大。