In ancient times, dogs were mainly helping people hunt( 打猎) .Now they are more useful-they can help the blinds, search for the bad eggs.
A. bad for
B. used to
C. used for
D. good at
网友回答
A. bad for
B. used to
(答案→)C. used for
D. good at
解析：考查词语辨析。be bad for“对…有害”； be used to do“过去常常做…” be used for doing “被用来干…” be good at doing“擅长干…”句意为“在古代，狗主要用来帮人们打猎。现在，它们更有用—能帮助盲人，搜寻坏蛋…”故选C。