孩子们在操场上跑出了一个完美的环形轨迹。

The kids ran in a perfect ___looping circle on the playground.

视频教程设置为循环播放模式，方便反复学习。

The tutorial video is set to ___looping mode for repeated viewing.

飞行员在空中做了一个完美的翻圈飞行表演。

The pilot performed a perfect ___looping in the airshow.