Finally the slave trade was in 1807.
A:analyzed
B:announced
C:abolished
D:assessed
①要发挥意识对改造客观世界的指导作用 ②要敢于突破思维定势
③要有革命的批判的创新意识 ④要敢于寻找新思路
喜马拉雅山系是由以下哪两大板块挤压形成的( )