Complex sentence: They were primarily divided into three categories a. Insomnia b. Hypersomnia and c. NightmareIin ninteenth century.t was following technological discovery in twentieth century specially last 50 years there is rapid advance in understanding and recognition of sleep disorders.
Split into simpler sentences: They were primarily divided into three categories a. Insomnia b. Hypersomnia and c. Nightmare. It was following technological discovery in twentieth century specially last 50 years there is rapid advance in understanding and recognition of sleep disorders.