下列属于世界人口稠密区的是( )
A:青藏高原
B:格陵兰岛
C:南极洲
D:我国东部平原
Many a student __________ wearing MP3 players while walking on the street. It's quite dangerous. ( )
(2016•江苏) 图6 为某主题公园所在城市分布图。图示5 个城市中( )
按要求排列.
1.212,1.212121……,1.21222……,1.212212……
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