the students could not have a picnic last saturday because i

the students could not have a picnic last saturday because it rained
it rained last saturday so it()()for the students to have a picnic
用get away,stand up,put into的正确形式填空
we had no time to take a photo of the beautiful car before she()
we do not know what tom()his bag before he left the room
everyone()when sun yang jumped onto the podium
已知x=4,y=3是方程组ax+by=5,bx+ay=-12的解,则a+b
如果不等式3x-m≤0的正整数解是1,2.3,那么m的范围
因式分解
2a（x²+1）²-2ax²
2x²+2x+二分之一