I am very grateful ______________ the dog. [ ]
A. at
B. of
C. to
答案:C
常用于消毒的紫药水是高锰酸钾(KMnO4)的稀溶液.KMnO4中锰元素的化合价是( )
A.+2
B.+6
C.+7
D.+4
Special attention should be _____ to air pollution wherever the factory will be built.
A.made
B.paid
C.taken
D.sent