(someone) needs to mellow out

Translations
(кому-то) нужно расслабиться
He needs to mellow out before the big presentation.
Ему нужно расслабиться перед важной презентацией.
Definitions
This phrase means that someone should relax, calm down, or become less tense, angry, or stressed. It is often used when a person is acting overly emotional, agitated, or intense, suggesting they need to take it easy.
Words
someone

pronoun
кто-то
needs

verb
нужно
to
чтобы
mellow

verb
расслабиться
out

adverb
полностью