大家好，請教一下
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.

癥結是你只擷取一個小段落，所以只能靠你給的內容來「猜」。那串Tdol講的是一個的可能，但是和影片內容不符合。「我猜」是四組動作是一個rep(剛好和影片約0:05, 0:06處的"剪接"符合 -- 邊做邊念 1,2,3,4,5,6,7,8(轉左), 2(再轉左一次，也就是change sides，開始另一個rep),2,3,4,..但是這和後頭的第二個"剪接"對不上。總之需要完整內容才能確定(也許How to Change Sides是指你沒給的部份，也許....)(我只是說個大概，我對這沒興趣所以你不需要找來貼不過你倒是可以給那邊英語人士較完整的內容)

感謝D大！