 Similarly, the three characters (Middle Chinese ) are now pronounced ', with tones 1, 2 and 4.The four characters (Middle Chinese ) are now pronounced ', with tones 1, 2, 2 and 3.In those cases, the two sets of characters are significant in that each member of the same set has the same phonetic component, suggesting that the phonetic component of a character has little to do with the tone class that the character is assigned to.