The tonal categories of modern varieties can be related by considering their derivation from the four tones of Middle Chinese, though cognate tonal categories in different dialects are often realized as quite different pitch contours. Middle Chinese had a three-way tonal contrast in syllables with vocalic or nasal endings. The traditional names of the tonal categories are "level"/"even" ( '), "rising" ( ') and "departing"/"going" ( '). Syllables ending in a stop consonant , or (checked syllables) had no tonal contrasts but were traditionally treated as a fourth tone category, "entering" ( '), corresponding to syllables ending in nasals , , or .