"博学"在英语中可以用 "widely learned" 或 "erudite" 来表示。

"Erudite" 源自拉丁文 "eruditus"，意思是 "well-educated" 或 "having extensive knowledge acquired through reading and study". 例如：

He is an erudite scholar, with a deep understanding of history and pterature. 他是一位博学的学者，对历史和文学有深入的了解。

She is an erudite speaker, with a wealth of knowledge on a wide range of topics. 她是一位博学的演讲者，拥有广泛主题的丰富知识。

"Widely learned" 意思是 "having a lot of knowledge from many different sources"。例如：

He is widely learned, with a broad range of interests and expertise. 他博学多才，兴趣广泛，专业知识深厚。

She is a widely learned scholar, with a deep understanding of both science and the arts. 她是一位博学的学者，对科学和艺术都有深入的理解。