0 short form of who had: --
Well, who'd have thought Joey was going to become so successful?
She wondered who'd sent her the mysterious email.
1 contraction of who would or who had: --
It’s about a boy who’d (= who had) been around the world.
Who’d (= Who would) have thought we’d be married for this long?
He is the man who'd never been on a plane.
He asked who'd unlocked the door.
Who'd have thought that Kevin would do so well?
I wondered who'd written the note.
Who'd like another piece of cake?
NYA ORD
European
May 10, 2021
DAGENS ORD
Shimmer
who'd