下列命题中,真命题是( )
A:a2+(2a)2=(a-3)2+(2a-1)2
B:a=1
C:a+b=0的充要条件是a= -1
D:a>1且b>1是ab>1的充分条件
It was with his iron-fist approach crimes in the southern state _______the 70-year-old man built a political name.
阅读课文《走一步,再走一步》,结合语境解释下列词语,有误的一项是( )
Are these ?