Mining backfilling is restrained by relatively high filling cost.充填采矿由于充填成本较高而制约着其发展.High - water rapid - hardening backfilling with whole tailings is a new developed backfilling technology.全尾砂高水速凝充填技术是一项新近发展起来的充填技术.Its ...
Again Martin seemed untroubled, yet Celia detected strain beneath the surface.马丁仍然显得无忧无虑, 但西莉亚察觉到了他内心的焦虑.He seemed to be quite untroubled by the news.听到这消息以后,他好象并不担忧.At first, the Supreme Court seemed untroubled by causa...
In August 1935 , we began our march across the marshy grassland.1935年8月, 我们开始过草地.There is a reach of grassland in the distance.远处是连绵一片的草原.Animal husbandry on the grassland is developing rapidly.草原上的畜牧业在迅速发展....