灭磁系统由()、()及灭磁回路开通控制单元组成。
参考答案:灭磁开关;灭磁电阻
在海上,灯塔位于一艘船的北偏东40度方向,那么这艘船位于这个灯塔的[ ]
A.南偏西40度方向
B.南偏西50度方向
C.北偏东50度方向
D.北偏东40度方向
It has been many years since I was last in London, _______ I still remember something that happened during that visit.
A.and
B.for
C.but
D.as