The
four tones of
Chinese poetry and
dialectology are four traditional
tone classes of
Chinese words. They play an important role in
Chinese poetry and in comparative studies of tonal development in the modern
varieties of Chinese, both in traditional Chinese and in Western
linguistics. They correspond to the
phonology of
Middle Chinese, and are named
even or
level (平
píng),
rising (上
shǎng),
departing (or
going; 去
qù), and
entering or
checked (入
rù). (The last three are collectively referred to as
oblique 仄 (
zè), an important concept in poetic
tone patterns.) Due to historic splits and mergers, none of the modern varieties of Chinese have the exact four tones of Middle Chinese, but they are noted in rhyming dictionaries.