Verbseoul.
하다 verb (adj)
담담하다damdamhadacalm

To say calm politely in the present tense, use 담담해요 (dahm-dahm-hae-yoh). Below is the full conjugation of 담담하다 across the three tenses and three everyday speech levels.

Conjugation table

TenseCasual (반말)Polite (요)Formal (합니다)
Present
담담해
dahm-dahm-hae
담담해요
dahm-dahm-hae-yoh
담담합니다
dahm-dahm-hahm-nee-dah
Past
담담했어
dahm-dahm-hae-ssuh
담담했어요
dahm-dahm-hae-ssuh-yoh
담담했습니다
dahm-dahm-hae-sseum-nee-dah
Future
담담할 거야
dahm-dahm-hahl- -guh-yah
담담할 거예요
dahm-dahm-hahl- -guh-yae-yoh
담담할 겁니다
dahm-dahm-hahl- -guhm-nee-dah

Other useful forms

Command Polite (세요)
담담하세요
dahm-dahm-hah-sae-yoh
Suggestion / Let's Polite (요)
담담해요
dahm-dahm-hae-yoh
Question Polite (요)
담담해요?
dahm-dahm-hae-yoh-?
Connective “and” — (고)
담담하고
dahm-dahm-hah-goh
Conditional “if” — (면)
담담하면
dahm-dahm-hah-myuhn
Noun form — (기)
담담함
dahm-dahm-hahm