高炉炼铁时使用的铁矿石主要是烧结矿、球团矿和（）
A．澳矿
B．海南矿
C．天然富铁矿
参考答案：C
猪棘头虫的中间宿主是（）
A.金龟子
B.淡水螺
C.扁卷螺
D.钉螺
E.土蜗螺
In his first class,the Chinese teacher tried to_______to children that reading is one of life's greatest
pleasures.[ ]
A. convey
B. educate
C. persuade
D. convince
