How do you say 'take a deep breath' in Japanese?

口臭 (koushuu) is the Japanese Word for "bad breath". So to say someone has bad breath, you can say 君は口臭がある (kimi ha koushuu ga aru) which means "You have bad breath". A couple other ways you could say the person has bad breath are 君の口臭がひどい (kimi no koushuu ga hidoi) which means "Your breath is terrible" and 君の息が臭い (kimi no iki ga kusai) which means "Your breath stinks".