Iron ores of greatest economic interest contain magnetite and hematite.最具有经济价值的铁矿包括磁铁矿和赤铁矿.It'sensed a mineral called hematite that often forms under wet conditions.发现一种被称作赤铁矿的矿物质,一般是在湿润的环境下形成的.Factors influencing t...
Rotary's primary responsibilities include fundraising, advocacy, and volunteer recruitment.扶轮主要的责任包括了募款 、 倡导和招募义工.They would do well to pause and ponder upon their new responsibilities.人们最好还是停一停,好好地想一想自己所负的新责任.The r...