Meaning of maintain in English
1. keep something in a good condition by checking or taking care of it regularly
maintain a road[building, website, garden, ...]
2. continue something and not let it come to an end
maintain peace and order
We must maintain friendly relations between Japan and China.
3. keep stating that something strongly be true or wrong, even if other people do not agree or do not believe you; assert
She maintained it to be true.
4. support someone’s rights, point of view, opinion etc.
maintain an argument[opinion, ...]
Food is necessary to maintain life.