The phrase "are mostly painted with" is correct and usable in written English.
It can be used to describe the predominant colors or techniques used in painting something, often in an artistic context.
Example: "The walls of the gallery are mostly painted with vibrant hues that capture the essence of the artist's vision."
Alternatives: "are primarily coated with" or "are largely adorned with".
Because the color white is associated with death in China, the walls are mostly painted in yellow and pink tones.
The initial cover art was mostly painted by Howard Brown, but when Earle K. Bergey began to paint covers for Startling in 1940, soon after its launch, Bergey quickly became identified with the magazine; between 1940 and 1952 (the year of Bergey's death) he painted the great majority of covers.
My grandmother was an artist, she mostly painted with watercolors.
The characters I paint are mostly male, preferably fat and hairy.
"It's mostly about painting an unacceptable contrast," Mr. Shaw concluded.
Though, I was mostly involved with painting and analogue technics, at that time, I was experimenting with a lot of different stuff aside most of the time.
"Everything has to come to an end someday," one driver, Juan Estanciola, said on a recent day outside his modestly painted bus, which is mostly white with purple trim and bears sayings like "Don't let my presence mess with your mind".
One of the compartments was painted grey; the other was painted with vertical black and white stripes.
The majority of the 256-color backgrounds in the game were mostly mouse-drawn with Deluxe Paint, though roughly ten percent were paintings scanned at the end of the development cycle.
The front of the restaurant is mostly glass, latticed with strips of wood painted the lulling blue of a Mediterranean sky, and on a warm night whole sections of this transparent wall open, erasing the division between inside and out, letting gentle breezes and the faint bustle of a narrow SoHo street wash over you.
