private void insertPuncInPunc(TextBlock tb, char c, int cp) {
tb.insertCharacter(c, cp);
caretBlock = tb;
caretPos = cp + 1;
}
private void insertLetterInWord(TextBlock tb, char c, int cp) {
tb.insertCharacter(c, cp);
caretBlock = tb;
caretPos = cp + 1;
}