粒子移动方向是()
A.直线的方向
B.与平面平行的方向
C.与面垂直的线的方向
D.以上说法都不正确
参考答案:C
简述面部整形手术切口线的设计原则。
She couldn't help, even though she tried not to,()at the strange clothes her friend was wearing.
A. to laugh
B. laugh
C. laughing
D. laughed