godan verb (-tsu), transitive verb
Transitive: actively keep something in a certain state, preserve it, or maintain it over time. Often used with abstract nouns like 健康, 秩序, 関係.
健康を保つために、毎日運動している。
I exercise every day to maintain my health.
両国は長年友好関係を保ってきた。
The two countries have maintained friendly relations for many years.
godan verb (-tsu), intransitive verb
Intransitive: something lasts, endures, or stays in good condition without external effort. Common for food, goods, or abstract states.
このパンは冷凍すれば一ヶ月は保つ。
This bread will keep for a month if frozen.
彼の集中力は長くは保たなかった。
His concentration didn't last long.