A:三公九卿制
B:三省六部制
C:权力高度集中
D:法律细密、严苛
若两个非零有理数a,b,满足|a|=a,|b|=﹣b,a+b<0,则a,b的取值符合题意的是( )
Yesterday an old man's house was _______fire. And now he is_______ hospital.