keep one's chin up

keep one's chin up — не падать духом, не отчаиваться, не вешать нос

Chin up! {infml}
Something you say to someone in a difficult situation in order to encourage them to be brave and try not to be sad.
Не вешай нос!
Не падай духом!
Не отчаивайся!
Держись!

Examples: Chin up! It'll soon be the weekend.(CALD)

Keep your chin up. Don’t let your chin hang down in discouragement; keep
your chin and your pecker up
Keep your pecker up.Chin up! (= Don’t hang your head down in despair; look cheerful; hold your chin and nose up in the air and don’t let the world know that you care.)
.

Examples from Idioms and Expressions by David Holmes: …Don’t allow yourself become depressed. Hold your head high and keep your pecker up.
...Always keep your pecker up, and never let people see when you are discouraged.

Keep the faith (=Don’t give up confidence in the struggle; keep on fighting for what you believe in)

Keep on plugging. Don’t stop trying your best.
Keep plodding on. Keep going despite the drudgery

Keep up the good work. Continue doing the same kind of good work