Complex sentence: Chan's early works are mostly small drawings in pen and ink, color pencils, pastels and markers on paper while he constantly educates and refines himself in skills and switches to large-scale acrylic paintings in his more recent works.
Split into simpler sentences: Chan's early works are mostly small drawings in pen and ink, color pencils, pastels and markers on paper. He constantly educates and refines himself in skills, and has switched to large-scale acrylic paintings in his more recent works.