CAE 2 (OW) | U6: Modals in the Past
You wake up to find your phone in the fridge. What *** happened?
may/might/could have
Speculate > Your neighbor suddenly moves out in the middle of the night without telling anyone.
They might/may/could///must have...
Speculate > You see your best friend crying their eyes out in the middle of the street.
They might have broken up with their crush.