A pile of sand is loose, but it and cement, gravel, water mixture, than the granite also tough.
一堆沙子是松散的，可是它和水泥、石子、水混合后，比花岗岩还坚韧。
2
This paper discusses the method for cutting cementing and flushing core samples from a loose oil-bearing sandstone reservoir, and the formulation of an inorganic cement.