Hi;
These are very good clips about Yi Jing Jing.
as they show you how to do these moves/postures slowly in the beginning,
the left posture and the right posture and then side view as well.
For the most part, the teacher is saying how to do these moves and focus on qi.
In general there are 3 levels of doing these postures.
We may slightly bend the knee or the back, we may bend more and finally we may bend all the way.
This applies to all the postures.
For the most part, it is stretching all of your joints and add more flexibility around your spine, too.
In turn, your internal organs are "massaged" and replenished with 02 or Chi.
Every thing has to be done gradually so that injuries will not occur.
A guidance from a good teacher is absolutely reccomended.