Read each sentence and choose the correct type of it

1. If people don't understand each other because of age difference, it means they have generation gaps.[zero|first|second]
2. If you don't care about marks and often come late for classes, you will soon get bad performance at school.[zero|first|second]
3. If you don't want to get lost in an unknown city, you need to download a special app or take a map with you.[zero|first|second]
4. You would win this game unless you were so absent-minded.[zero|first|second]
5. If you want to stop sibling rivalry with your sister, you should not compete but communicate with her. [zero|first|second]
6. If you tried to understand each other's needs, you wouldn't quarrel so often. [zero|first|second]