By the time they returned the books // the party started.
After Simon had eaten // someone had cleaned the house.
Once she had stoked the fire // the library had already charged them.
When he returned from the gym // the room warmed up.
The vault had been emptied // before he studied at university.
He hadn't read as many books, // by the time the police arrived.
She had waited for the call all day, // things had been much better.
After Stephanie had returned from the hospital, // since she heard the news.