直流发电机的主磁极是产生磁通的部件。
参考答案：对
刺激肝脏细胞分泌急性期蛋白的因子是（）.
A.IFN-α、TNF-α
B.TNF-α
C.IL-2、IFN-，γ、TNF-α
D.IL-6
E.IL-6、IL-1
After graduation she reached a point in her career _____ she needed to decide what to do. [ ]
A. that
B. what
C. which
D. where
