问题
选择题
Could you put the book ____________ the desk?[ ]
A. to
B. for
C. from
D. on
答案
答案：D
搜题请搜索小程序“爱下问搜题”
Could you put the book ____________ the desk?[ ]
A. to
B. for
C. from
D. on
答案：D
，该氧化物中Cr为＋6价