用平行投影法沿物体不平行于直角坐标平面的方向,投影到()上所得到的投影称为轴测投影。
A、平行投影面
B、中心投影面
C、轴测投影面
D、多个投影面
参考答案:C
Three-fourths of the homework ____ today. [ ]
A. has finished
B. has been finished
C. have finished
D. have been finished
杭州哺乳假多长时间?现在还有吗?