It can be described like this.

Idiom: to speak with certainty

Pinyin: yán zhī záo záo

Explanation: to speak with certainty: indeed. The description is very precise.

Source: Qing Dynasty Pu Songling's "Liao Zhai Zhiyi·Duan": "The words are conclusive and credible."

Synonyms: absolutely true, beyond doubt, ironclad evidence Like a mountain

Antonyms: catching wind and shadows, castles in the sky, fishing for the moon in the water

Grammar: subject-predicate form; used as predicates and clauses; to describe well-founded speech