Whenever necessary, I would do some marking in the book, using colour pens and even taking down notes in a separate exercise book for future reference.

必要时，更在书本上做记号，用彩色笔加上五颜六色，甚至在本子上另做笔记，以备日后参考。

youdao

The neatly designed, New York City-style blocks explode with colour, sound and traffic - marking the spot where Western order and African energy intersect.

BBC: Transforming from Johannesburg to Jozi

The photograph was first seen at King's College London during a Royal Institution lecture on colour theory by the Scottish physicist James Clerk Maxwell on the 17 May 1861 and the college is marking the 150th anniversary of that demonstration with an evening of talks celebrating his scientific discoveries.

BBC: Pioneering colour photography