Помогите, пожалуйста воткнуть предлоги в предложения.1. You should praise them ...

Помогите, пожалуйста вставить предлоги в предложения.
1. You should praise them ... their work.
2. Quite ... accident we met in the corridor.
3. She made an emotional appal ... her son's behalf.
4. Who is the heir ... the throne?
5. You should sign ... before entering.
6. Donna has ben suffering ... headaches for two or theree years.
7. She's decided to sign ... for musical classes.
8. Success in school inspired me ... hope ... the future.
9. We inherited the house ... our grandparents.
10. You need your password to sign ... .
11. Could you hire a taxi for me while I'm signing ... .
12. It's time for me to sign ... now. Goodbye.