Complex sentence: Libyan Arabic is not normally written, as the written register is normally Modern Standard Arabic, but Libyan Arabic is the main language for cartoonists, and the only suitable language for writing Libyan folk poetry.
Split into simpler sentences: Libyan Arabic is not normally written, as the written register is normally Modern Standard Arabic. But Libyan Arabic is the main language for cartoonists, and the only suitable language for writing Libyan folk poetry.