—Where's the bag?
—I _____ know.[ ]
A. aren't
B. am not
C. isn't
D. don't
答案:D
气滞痛的特点是:
A.游走性,痛无定处B.阵发性,攻痛无常C.随情绪波动而时时作痛D.胀痛E.持续性固定性胀痛
所有带接地的灯具都必须通过接地电阻测试。