http://v.youku.com/v_show/id_XNTE0MDk1Mzg0.html
Many of the incorrect demonstrations have more than one issue—they’re full of problems from head to toe. So the answers should be open-ended, and everyone is welcome to freely critique and share their opinions.
Below are some of my own thoughts, which may not all be correct. Thanks to Snowkela for some additional insights:
1. Snowplow stance. Weight is too far inside, with the inside foot bearing too much load. The weight should be tilted slightly outward. You can try the "airplane" exercise.
2. Small turns where the arc isn’t smooth (or doesn’t really turn at all). Weight lags behind. It’s recommended to break down the movement, start over from scratch, and choose gentler slopes to complete the turns properly.
3. The one dressed like a fake instructor. Upper and lower body aren’t separated, and the weight is still too far inside and backward. Shoulders need to be stabilized. It’s suggested to practice upper-lower body separation and twisting exercises.
4. The one skiing with legs together and poles stuck out. Again, there’s an issue with upper-lower body separation, so turning largely relies on leaning the upper body, which lacks efficiency.
5. The person in the orange clothes doing ski dancing. Their skills are decent, but their upper body sways too much. As Snowkela said, it’s "swaying back and forth and side to side."
6. This one is a bit hard to describe—her technique is actually pretty good, and perhaps from another technical perspective, her movements aren’t wrong. I think she lacks the necessary counter-rotation, so during a certain part of the turn, there’s very little edge pressure on the board, making control over that section quite weak.