IT系统是中性点不接地或经高阻抗接地的系统。设备外露导电部分（）。

A.不接地

B.接地

C.经小电以接地

D.经小电容接地

By the following semester, it is likely that the old professor______on the campus of Califor nia University for two decades.

A．will have to be teaching

B．will have been taught

C．will have been teaching

D．will be teaching