YOU _______________________ (NOT TIDY) YOUR BEDROOM WHEN I GOT HOME.
You WEREN'T TIDYING your bedroom when I got home.
MUM _________________ (PREPARE) THE DINNER AT 9 O'CLOCK.
Mum WAS PREPARING the dinner at 9 o'clock.
________ THE DOG ___________ (SWIM) IN THE POOL ? YES, IT _______.
WAS the dog SWIMMING in the pool? Yes, it WAS.