问题补充：
—Do you think a radio is useful in learning English?
—Sure. A radio can listening English songs and reports.
A. be used by
B. be used as
Cbe used for
D. be used to
答案：
A. be used by
B. be used as
(答案→)C. be used for
D. be used to
解析：句意：上句问你认为收音机在学英语方面有用吗？下文是的，收音机能用来听英语歌曲和报告。be used as被当作……用be used for被用来干……= be used to do be used to doing习惯做……=get used to be used by …被用来做什么？its no use doing sth做……是没用的。故选C
