What should I say when the teacher sends a video of the child running?

In this case, here are some possible answers:

1. Thank you for sharing your child's running video. The child behaved well and worked hard.

It's really nice to see the children making progress in running. Thank you for your careful teaching and encouragement.

3. Children still have a lot of room for improvement in running. I hope teachers can give more guidance and help, so that children can better play their potential.

4. Children's running posture and breathing style need to be practiced. I hope that teachers can give more guidance and make more corrections, so that children can train more scientifically.