keep A1

/kiːp/ To continue to have something and not give it away.

keepsake C2+

/ˈkipseɪk/ a small item kept in memory of the person who gave or owned it

keeping C2+

/ˈkipɪŋ/ care, custody, or harmony with something

upkeep C2+

/ˈʌpkip/ the cost or process of maintaining something in good condition