The field coils ______ and the armature(电枢) ______. This is in fact the arrangement adopted for large, heavy duty alternators.
A. are stationary(固定的)/rotates
B. are stationary/is stationary
C. rotate/ is stationary
D. rotate/rotate
The engineer ______ the watch to the relieving officer if there is reason to believe that
A. shall take over
B. shall not take over
C. shall hand over
D. shall not hand over
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