"Writhing"

[Odessa Dawn]

Mark 9

¹⁸And whenever this spirit seizes him, it throws him violently to the ground. Then he foams at the mouth and grinds his teeth and becomes rigid.* So I asked your disciples to cast out the evil spirit, but they couldn't do it."

¹⁹ Jesus said to them,* "You faithless people! How long must I be with you? How long must I put up with you? Bring the boy to me."

²⁰ So they brought the boy. But when the evil spirit saw Jesus, it threw the child into a violent convulsion, and he fell to the ground, writhing and foaming at the mouth.

I checked YOUTUBE, and found foaming at the mouth. Also, teeth grinding is easy to be understood. But I couldn’t figure out "Writhing." I do know what is "Writhing" look like in my native language, but it depends on the situation. Do we have a video in which I could understand the exact meaning of "Writhing" in English and how the person becomes when s/he experiences "Writhing?" Will you clear it up, please?
writhe verb - definition in British English Dictionary & Thesaurus - Cambridge Dictionary Online

Definition of writhe | Collins English Dictionary

writhing - Dictionary Definition : Vocabulary.com

Please not that sometimes I come across such a situation and I help people drive them to hospital particularly those who are homeless and needy. However, when we reach hospital, I told that those people aren’t sick. Besides, hospital staff crush us and no an admission allowed. Therefore, I have been told a lot of times not to bring them to hospital. I started thinking about that. When I read Mark 9:18-20, I remembered those people. So, the word "Writhing" needs to be mastered. I hope you understand me.

[5jj]

Cat writhing on the kitchen floor - YouTube