如数家珍 (如數家珍) rú shǔ jiāzhēn

rú shǔ jiāzhēn set phrase as if counting family valuables; very familiar with the matter
Domain: Idiom 成语 , Concept: Person 人
Notes: (CC-CEDICT '如數家珍'; Guoyu '如數家珍'; Han Dian '如数家珍')