exposition/ˌek.spəˈzɪʃ.ən/名词展览会;博览会;商品交易会the San Francisco exposition旧金山博览会清楚详尽的解释;详细阐述It purports to be an exposition of Catholic social teaching.它旨在详细阐述天主教的社会教义。想跟读,去练习