savoir de quel bois quelqu'un se chauffe

== French == === Etymology === Literally, “with what wood someone is heated” === Pronunciation === IPA(key): /də kɛl bwa kɛl.k‿œ̃ s(ə) ʃof/ === Phrase === de quel bois quelqu'un se chauffe (informal) what someone is made of, what someone is capable of, someone's true mettle Synonym: ce qu'on a dans le ventre montrer de quel bois on se chauffe ― to show one's mettle ==== Usage notes ==== Chiefly used with the verbs montrer, voir and savoir.