It is striking that tone symbols and some vowels are included
several times in the table. Why? They are located at different
heights in the character set, so that a suitably equipped
program can construct the signs more tightly together. Example:
A consonant without a vowel, but with a tone
symbol is usually written as:
At least the keyboard generates the default code for that.
An intelligent program could recognize, however, that the
reserved space for a vowel is not required in this case, and
replace the tone mark with a lower position for displaying
The replacement should not take place if the
consonant has a vowel already:
otherwise it will result in .