— No. It has to be put off(推迟) ________ the heavy rain.
A:because
B:because of
C:such as
D:although
下列各句中划线的成语使用不当的一项是( )
已知椭圆x2a2+y2b2=1a>b>0的离心率e=12,右焦点为Fc,0,方程ax2+bx-c=0的两个实根x1,x2,则点Px1,x2( )