A本题考查介词辨析。空格处填入一个介词,后面接名词短语a Roman priest,过去分词named Valentine作后置定语修饰priest。[A]after意为“模仿,依照”,如:We named the baby after her grandmother.(我们以婴儿祖母的名字给婴儿取名。)该用法符合文意,空格所在句子相当于Valentine’s Day was named after a Roman priest。其它项虽然都可作介词,since“自从”,as“作为”,from“从”,但不