她曾经对这个问题深深思考过。

She had thought very deeply about this problem.

《牛津词典》

如果说有哪部电影能让你在看完后对着镜子陷入深深思考，那毫无疑问就是它了。

If there is a film that makes you take a deep look at yourself in the mirror again and again, this is it.

youdao

The text into which any early modern seventeenth-century writer would jot his or her thoughts into, his reading notes, was always called a commonplace book.

他的阅读笔记,那是许多早期的十七世纪现代作家都会深深思考的笔记，它常常被称为一本普通的书。

耶鲁公开课 - 弥尔顿课程节选