综合北京大学东方学系张光麟教授和令恪先生所述,季羡林的学术成就大略包括在以下10个方面:(1)印度古代语言研究——博士论文《〈大事〉渴陀中限定动词的变化》、《中世印度语言中语尾-am,向-o和-u的转化》、《使用不定过去式作为确定佛典的年代与来源的标 According to Professor Zhang Guanglin and Mr. Ling Zhu from the Department of Oriental Studies, Peking University, the academic achievement of Ji Xianlin is roughly covered in the following ten aspects: (1) Studies of ancient languages ​​in India - Doctoral Dissertation “Changes in the Qualified Verbs” , “The end of the lingo in the Middle Ages dialect-am, the transformation to -o and -u”, "the use of indefinite past tense as a criterion for determining the era and source of the Buddhist scriptures