Sinopie are preliminary sketches or drawings, especially those done on plaster in preparation for a fresco.
Sinopie are important for making art. They are like the first ideas for a big painting.
Examples:
The artist made sinopie on the wall before painting the big picture.
Sinopie help the artist plan the painting.
The sinopie are the first drawings for the big painting.
The sinopie are like the first ideas for the big picture.
The sinopie are the most important part of the painting.
The sinopie are like the first words of a big story.