A:Mg2+
B:Zn
C:Al3+
D:2Cu
罗马帝国灭亡后,欧洲的精神领袖是( )
He used to __________ in a small village, but he has been used to __________ in a big city now.
下列对课文《与朱元思书》的理解和分析有误的一项是( )