下列属于古今字的是（）。
A. 孰—熟
B. 责—债
C. 阙—掘
D. 反—返
E. 辟—避
Now the college often trains their students for posts or positions.(specify)
Please the materials to my office computer through QQ or e-mail?(communication)
Copper electricity better than other materials. (conduct)
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