major in的用法和樣例：
例句
- He majors in Russian literature.
他主修俄羅斯文學。 - English is his major and history is his minor.
他主修英文，副修歷史。 - Many students specialize in engineering.
許多學生專攻工程學。 - I'm majoring in business administration in college.
在大學里我專攻商業管理。 - I majored in English but now I major in French.
我曾專修過英語，但現在我主修法語。 - Mike specializes in the history of fashion at the university.
邁克在大學里專修時裝史。
