圆柱的侧面展开一定得到长方形或正方形．
— Alice, could you help me ________ the meat? I want to make some dumplings for dinner.
— OK. I'll do it right away.
把草履虫的结构与相对应的功能用线连起来．
读我国东部某地区等高线地形图（单位：米），完成各题．
