很瘦的瘦怎么说英语

If you want to describe someone as being very thin in English, you can say that they are "very thin" or "extremely thin." You could also say that they are "very skinny" or "extremely skinny." For example:
She is very thin.
He is extremely thin.
She is very skinny.
He is extremely skinny.
Note that it's generally not considered polite to comment on someone's weight or appearance, so it's important to be mindful of how your words might be perceived.