There are a lot of idiomatic expressions in English relating to skin and bones. Here are a few examples.
Bone idle – lazy. (Example: He never does anything; he’s just bone idle.)
Bone up – study. (Example: I need to bone up on history before the final exam.)
By the skin of your teeth – barely. (Example: I caught the cab by the skin of my teeth. It was about to pull away.)
Close to the bone – offensive, painful or personal. (Example: I get a bit uncomfortable with Bob, because his comments are always close to the bone.)
Get under your skin – irritate or annoy. (Example: He is one of the most irritating people I know. He really gets under my skin.)
Have a bone to pick – have a complaint. (Example: I have a bone to pick with you. You gave me the wrong directions to the concert and I missed the start. )
Jump out of your skin – to be shocked or surprised. (Example: When the serial killer appeared in the movie, I jumped out of my skin.)
Make no bones – speak frankly. (Example: I make no bones about saying that the movie was terrible. )
No skin off my nose – it doesn’t matter to me. (Example: It’s no skin off my nose if you’d rather be alone.)
Save your skin – get away from a dangerous or unpleasant situation. (Example: The soldiers started to fire but I managed to save my skin by hiding in the bushes.)
Skin and bones – very thin. (Example: She never gains weight. She’s just skin and bones.)
The bare bones – the outline. (Example: The professor gave the students the bare bones of the topic and told them to read up on the rest. )
Work your fingers to the bone – work hard . (Example: While you went to the party, I worked my fingers to the bone tidying up the house.)
Can you think of any to add?