荡秋千的运动方式是旋转．______．
荡秋千的运动方式是旋转现象；
故答案为：√．
—What were you doing when the rock star arrived?
— .[ ]
A. I was doing my homework
B. I am doing my homework
C. I do my homework
D. I did my homework
什么是监控摄像机的光谱响应特性？
