Liu's recreations of paintings of Pablo Picasso's Untitled. [Photo provided to China Daily]

Painting skills need daily practice, but due to the school's closure as a social distancing measure to curb the spread of the pandemic, Liu came up with this way of practicing painting after he returned home.

To fill the day, when passing the wall in January, the 22-year-old found that "the wall's rough and bumpy feel might be OK for oil painting".

Then came his first copy－The Fifer by Edouard Manet from 1866, "a salute to the French painter", according to the student.

"I have been deeply influenced by Manet's art style. Among his paintings, my favorite is The Fifer, which is brightly lit from the front with almost no shadow making it a flat painting," Liu says. "It can be seen as an expression of artistic innovation in impressionism."

Every sunny day Liu has brought paints, palette and brushes to the wall and finished three or four copies, each of which took about 40 to 50 minutes.

To make the wall easier to paint, he adds turpentine and megilp to oil paint to add more thickness and richness to its pigment. He even spent two days smoothing the wall.

Liu says he hopes that he can complete painting the entire wall before the school reopens.

Liu's recreations of paintings of Portrait of D. M. [Photo provided to China Daily]