помогите пожалуйста разобраться с функциями инфинитива1. It was nice to be

Помогите пожалуйста разобраться с функциями инфинитива

1. It was nice to be speaking English again.
2.His intention was to get into parliament.
4. They must leave at noon.
5. Dan learned to read when he was five.
6. At times, the young man played the piano loudly enough to burst our eardrums.
7. We didn't have enough time to stay at the seaside for more than five days.
8. She nervously put her хэнд to her mouth as if to stop coughing.