- I'm tired. I want to have a day _________ next week.
- Great idea, honey. You do need a break.
A:away
B:on
C:off
血小板会释放出一种物质,使血液
已知关于x,y的方程组3x+y=1+3ax+3y=1-a的解满足x+y<0,则a的取值范围是( )
已知AB∥PQ,BC∥QR,∠ABC=30°,则∠PQR等于( )