A:经过两点有且只有一条直线
B:三角形的中位线平行且等于第三边的一半
C:平行四边形的对角线相等
D:圆的切线垂直于经过切点的半径
“I don't think it's my ________ that the window suddenly broke. I just opened it, that's all,” said the boy in tears.
下列日程是周恩来参加某次国际会议过程中其中一天的行程安排;这次会议( )
You can see a wide r____ of animals in the newly built zoo.
下列长江的支流中,最东边的一条是 ( ).