the shirt off someone's back

US /ðə ʃɜrt ɔf ˈsʌm.wʌnz bæk/
UK /ðə ʃɜrt ɔf ˈsʌm.wʌnz bæk/
"the shirt off someone's back" picture
1.

donner sa chemise, être extrêmement généreux

to be extremely generous, to give everything one has

:
He's so kind, he'd give you the shirt off his back if you needed it.
Il est si gentil, il te donnerait sa chemise si tu en avais besoin.
My neighbor is the kind of person who would give you the shirt off their back.
Mon voisin est le genre de personne qui te donnerait sa chemise.