A:a miss is as good as a mile
B:the grass is greener on the other side
C:it never rains but it pours
D:when in Rome, do as the Romans do
选出单词中不属于同一类的一项。
读“非洲河流分布图”和“非洲气候类型分布图”, 对甲、乙两河的描述,正确的是 ( )
南亚地形区的分布由北向南依次为( )
已知limn→∞an=3,limn→∞bn=13,则limn→∞an-3bn2an=____