已确诊肛裂时一般不宜行_________或_________，以免增加患者痛苦。
参考答案：直肠指检；内镜检查
在棱长为1的正方体上，分别用过共顶点的三条棱中点的平面截该正方体，则截去8个三棱锥后，剩下的凸多面体的体积是______．
My father is not here, you’d better call him ________ 3 p.m.________ 5 p.m. tomorrow.
A．from; and
B．from; to
C．between; and
D．between; to
