habt ihr vergessen, was

have you forgotten what

→ haben
phrase Rare #40,821
have you forgotten what Introduces a subordinate clause referring to something previously said, done, planned, or understood. The verb comes at the end of the subordinate clause.
GE: Habt ihr vergessen, was wir heute besprechen wollten?
EN: Have you forgotten what we wanted to discuss today?

Habt ihr vergessen, was mit Laxman passiert ist?

Have you forgotten what happened to Laxman?

— Gangs of Wasseypur - Teil 1 (2012)

Habt ihr vergessen, was Tom gesagt hat?

Did you forget what Tom said?

Habt ihr vergessen, was hier letztes Jahr passiert ist?

Have you forgotten what happened here last year?

Habt ihr vergessen, was wir vorhatten?

Have you forgotten what we were planning?

Habt ihr vergessen, was Tom getan hat?

Have you forgotten what Tom did?