A:三个物体所受的摩擦力大小相同
B:甲物体所受的摩擦力最大
C:乙物体所受的摩擦力最大
D:丙物体所受的摩擦力最大
—Is that a tiger?
— No. It's a monkey.
When leaders of Chinese mainland(大陆)and Taiwan met in Singapore for ________ first time since 1949, President Xi said, "Today will be remembered in _________ history."
陈胜在起义前对当时的形势作了精辟的分析,他是怎样分析和估计的,请简要述之。