双燃料发电机组停机状态保养最好每周或每两周运转一次以减少动力（）损失。
参考答案：端油膜
Jack had________feeling of excitement when hearing his article had been published in________school
magazine. [ ]
A. the; a
B. a; the
C. /; the
D. the; /
中经产业景气指数包括景气指数、预警指数和行业预警灯号。（）
