maintain

maintain /meɪnˈteɪn/ verb
maintains; maintained; maintaining
maintain
/meɪnˈteɪn/
verb
maintains; maintained; maintaining
Britannica Dictionary definition of MAINTAIN
[+ object]
1 
: to cause (something) to exist or continue without changing
2 
: to keep (something) in good condition by making repairs, correcting problems, etc.
3 
: to continue having or doing (something)
4 
: to say that (something) is true
5 
: to provide support for (someone or something)