文件的常规属性是指文件的()等。

A.大小

B.位置

C.类型

D.以上全部

Nowhere in nature is aluminium (铝) found free, owing to (由于) its always  ____with other

elements (元素) most commonly with oxygen.  [ ]

A. combined    

B. having combined 

C. combine    

D. being combined