Define the conditional in each sentence

1. If students don't care about marks and often come late for classes, they'll soon fail all the tests and exams.[zero|first|second]
2. If tourists don't want to get lost in Hong Kong, they need to download a special programme or take a map with them.[zero|first|second]
3. If you want to stop quarrelling with your sister, you should not make her annoyed.[zero|first|second]
4. If kids and parents don't understand each other because of age difference, it means they have generation gap.[zero|first|second]
5. They would win this competition unless their team had some weak players .[zero|first|second]
6. If they tried to understand each other's needs, they wouldn't quarrel so often.[zero|first|second]