I had written twice to Janet. But she didn't ______ my letters, so I decided to go there myself.
My manager told me ____ the same mistake again or I would be fired.
Tom ____ skating, so he spends all his spare time on it.
- Ann is in hospital. - Oh, really? I _______ know. I _______ go and visit her.
I told Sally how to get here, but perhaps I ___ for her.
The college entrance exam is ____ important to the student, and it’s also challenging.