1.What are your best ____(祝愿)?
2.Their ____ (工作) are standing and watching at the door.
3.My friends are coming ____(不久).
4.He____ (听) to the teachers carefully in class.
5.My friend ____(写信) to me three times a month.
如图所示,最左边的几何体由一个圆柱中挖去一个以圆柱的上底面为底面,下底面圆心为顶点的圆锥而得,现用一个竖直的平面去截这个几何体,则截面图形可能是( )
已知等比数列{an}的公比q=-13,则a1+a3+a5+a7a2+a4+a6+a8等于( )