Bonjour
1- ... when she arrived at work, Holly's aunt didn't know that day ...
2- When she sat down to her desk, he didn't know that she had a lot of work.
OU that she was having a lot of work.
Tout dépend du contexte.....
3- ....she was standing by the window when she heard an explosion.
4- She rushed out at once, and ran down the stairs.
5- Her husband was watching the news so he knew what happened.
Bonne journée