-- Whose is this sweater?
--
A:It's my.
B:It's my sister.
C:It's my brother's.
—Yes, I do. And l also know that some of them are scaring.
“这是…历史上的转折点,反西方国家联合起来在美国威信动摇时第一次彻底击败了美国。”材料中的“转折点”是指