A.范圍線; B.假想投影輪廓線; C.有特殊要求的線或表面表示線; D.軌跡線;
A.5:1; B.2:1; C.1:2; D.1:5;
A.螺距; B.導(dǎo)程; C.線數(shù); D.直徑;