混合气体，所需试剂有：
A．品红溶液 B．NaOH溶液
C．浓H2SO4 D．酸性高锰酸钾溶液
试回答下列问题：
A. Adults keep pets with their children.
B. Pet-keeping has a very long history.
C. Pet-keeping may do harm to animals.
D. People keeps pets for their aesthetic need.
E. Caged pets become increasingly popular.
F. Pet-keeping is helpful for children’s growth.
①遵循事物发展的客观规律 ②抓住主要矛盾的主要方面
③不失时机地促成质的飞跃 ④坚持普遍性与特殊性的统一
下列词语书写全都正确的一组是( )
