从结构层次上分析,老山羊比小白杨多了( )
A:细胞
B:组织
C:器官
D:系统
-- It's snowing. I really want to run outside and make a snowman.
-- Why not have a snow ball fight instead? It's more exciting.
学习历史,必须分清哪些是历史,哪些是观点.下列各项中属于观点的表述是( )