Language vs. Dialects Spoken Chinese comprises many dialects that can be classified in seven main groups. Although they employ a common written form, they are mutually unintelligible and for this reason are sometimes referred to as languages; the differences among them are analogous to the differences in pronunciation and vocabulary among the Romance languages. The fact is, however, that most Chinese speak the same dialect, which Westerners call Mandarin; its standard of pronunciation is the speech of Peking. Mandarin also forms the basis of the modern written vernacular, Baihua, which supplanted classical Chinese in the schools after 1917, and of the official spoken language, Putonghua, prescribed in 1956 for nationwide use in schools. For this reason Westerners usually speak of a single Chinese language.

The modern Chinese dialects (from the 11th century AD) evolved from Old (or Archaic) Chinese (8th-3d century BC), the sounds of which have been tentatively reconstructed. Although monosyllabic, Old Chinese was not wholly uninflected. The next stage of Chinese that has been carefully analyzed was Middle (or Ancient) Chinese (to about the 11th century AD). By this time the rich sound system of Old Chinese had progressed far toward the extreme simplification seen in the modern dialects. For instance, Old Chinese possessed series of consonants such as p, ph, b, bh (where h stands for aspiration or rough breathing). In Middle Chinese this had become p, ph, bh; in Mandarin only p and ph (now spelled b and p) are left.