大家好，请教一下
Exercise video:
https://youtu.be/3SRO7IQNHFI
Instructions for the exercise:
Starting Position
Sit upright on the ground with your arms crossed and knees bent. Lift your
feet off the ground.
Step 1
Twist so that your left elbow touches your right knee, then twist the other
way so that your right elbow touches your left knee.
Step 2
Go back and forth, without lowering your legs.
How To Change Sides
Alternate sides after each rep. Both sides must be exercised to count one rep
towards the goal.

症结是你只撷取一个小段落，所以只能靠你给的内容来“猜”。那串Tdol讲的是一个的可能，但是和影片内容不符合。“我猜”是四组动作是一个rep(刚好和影片约0:05, 0:06处的"剪接"符合 -- 边做边念 1,2,3,4,5,6,7,8(转左), 2(再转左一次，也就是change sides，开始另一个rep),2,3,4,..但是这和后头的第二个"剪接"对不上。总之需要完整内容才能确定(也许How to Change Sides是指你没给的部份，也许....)(我只是说个大概，我对这没兴趣所以你不需要找来贴不过你倒是可以给那边英语人士较完整的内容)

感谢D大！