1. Rosa Parks lived in/on the south of / to the USA.
2. She went at/to work by/on bus.
3. On buses, black people had to sit after/at the back.
4. Parks refused to give her seat on the bus at/to a white man.
5. Black people stopped using the buses in Alabama by/for 381 days.
6. After/to a year, the state changed the law.