Verbseoul.
하다 verb (adj)
차분하다chabunhadato be calm, to be composed, to be nonchalant

To say to be calm, to be composed, to be nonchalant politely in the present tense, use 차분해요 (chah-boon-hae-yoh). Below is the full conjugation of 차분하다 across the three tenses and three everyday speech levels.

Conjugation table

TenseCasual (반말)Polite (요)Formal (합니다)
Present
차분해
chah-boon-hae
차분해요
chah-boon-hae-yoh
차분합니다
chah-boon-hahm-nee-dah
Past
차분했어
chah-boon-hae-ssuh
차분했어요
chah-boon-hae-ssuh-yoh
차분했습니다
chah-boon-hae-sseum-nee-dah
Future
차분할 거야
chah-boon-hahl- -guh-yah
차분할 거예요
chah-boon-hahl- -guh-yae-yoh
차분할 겁니다
chah-boon-hahl- -guhm-nee-dah

Other useful forms

Command Polite (세요)
차분하세요
chah-boon-hah-sae-yoh
Suggestion / Let's Polite (요)
차분해요
chah-boon-hae-yoh
Question Polite (요)
차분해요?
chah-boon-hae-yoh-?
Connective “and” — (고)
차분하고
chah-boon-hah-goh
Conditional “if” — (면)
차분하면
chah-boon-hah-myuhn
Noun form — (기)
차분함
chah-boon-hahm