郭靖和杨康是金庸武侠小说《射雕英雄传》中的两个重要人物。这两位名字中的“靖”和“康”与下列哪一事件有直接关系( )
A:北宋建立
B:澶渊之盟
C:北宋灭亡
D:南宋建立
In western countries, when your friend offers (提供 )you something, you can accept it directly(直接地), or refuse it politely. Therefore, which situation fits the western custom?
—— ________ we go swimming in Xishuanghu Lake today?—— Oh, no. It's ________ cold to swim on such days. I will catch a cold.
用打点计时器研究小车在斜面上的运动,纸带记录如图所示,则小车运动的加速度大小是____ m/s2,打点计时器在打C点时,小车的速度vC=____m/s.
下列直接体现了我国处理民族关系原则的是 ()