sarebbero state

would be

→ essere
phrase Rare #32,869
would be Conditional form of essere for a feminine plural subject; used to report or describe what they would be or where they would be.
IT: Credevo che sarebbero state felici.
EN: I thought they would be happy.

Sapevano che sarebbero state in ritardo.

They knew they would be late.

Dissero che sarebbero state in ritardo.

They said they would be late.

Mi hanno detto che sarebbero state impegnate lunedì.

They told me they would be busy on Monday.

Hanno detto che sarebbero state in ritardo.

They said they would be late.

Noi non sapevamo su quale treno sarebbero state.

We didn’t know which train they would be on.

Pensavano che sarebbero state al sicuro qua.

They thought they would be safe here.

Mi hanno promesso che non sarebbero state in ritardo.

They promised me they wouldn’t be late.