opportunity是可数名词,其单复数形式明确且常用。表示“一个具体机会”时用单数,如“an opportunity”(例:She finally got an opportunity to study abroad);表示“多个机会”时用复数“opportunities”(例:Life is full of opportunities)。常见搭配如“seize an opportunity/seize opportunities”“miss an opportunity/miss opportuni...