Instead of you ___ on me. I should wait on you.
A.wait
B.waited
C.waiting
D.be waited
答案:C
如图所示的三自由度机械手(两个旋转关节加一个平移关节,简称RPR机械手),求末端机械手的运动学方程。
治疗筋脉挛急疼痛的药物,应选用的味是()
A.酸
B.苦
C.甘
D.辛
E.咸