钢铁厂购进含氧化铁(Fe2O3)85％的赤铁矿石1000t，准备用这些铁矿石炼取含杂质3％的生铁。
在保持水土方面起重要作用，并有“绿色水库”之称的是（ ）。
根据短文，判断正误。
Look at this desk. It's Jim's desk. It's brown. Jim's book is on it. It's an English book. His pencil-box is on it, too. His pencil is in his pencil-box. But where's his pen? He can't find it.
