考研考试

【单选题】 Nowhere in nature is aluminum found free, owing to its always ____________ with other elements, most commonly with oxygen.
A．combined
B．having combined
C．combine
D．being combined

网考网参考答案：D
网考网解析：
being combined是动名词，its是它的逻辑主语，合在一起构成动名词复合结构，作介词 owing to的宾语。 查看试题解析出处>>