根据句意及提示写词。
1. Her face was _______ (严肃的) as they told us the bad new.
2. We have to _______ (喊叫) because there are too much noise.
3. It's not _______ (安全的) to go out at night.
4. She spoke loudly in order to be h_______ clearly.
5. She was a v_______ of a road accident.