A:①②
B:①④
C:②③
D:③④
中国新民主义革命开始的标志是( )
While her mother was cooking, she ____ ____ ____ a good idea.
一次函数y=k1x+b1和y=k2x+b2的图象如图所示,自变量为x时对应的函数值分别为y1,y2.若﹣3<y1<y2,则x的取值范围是( )