根据短文内容及首字母提示，填入适当的单词，使短文的意思完整。（在填写答案时，单词的第一个字母要写出来）
    Have you ever seen Korean writing before? In many people's eyes, it  l____  lovely but difficult. Do you know the h____ of the special letters?
    Long ago, Korean people didn't  o____ their letters. At that time, they used Chinese characters(字符). Because Chinese is hard to learn, only rich people had the m____ and time to ask teachers to teach them. One of their kings was called Sejong. He decided to i____ Korean Letters. He thought hard.
    One day, on  O____  9, 1446, he looked at a window frame(框架)and shouted, “I know what our letters should be!” He was so excited that he cried it loudly. He got the i____from the frame and invented letters of all the same size. It seemed that they were put in a window frame. The  earliest Korean letters were born. King Sejong said, “Chinese characters can’t express Korean  meanings. Now I invent  o____  own letters. These letters are very  e____  to learn. I hope that they can help all people learn to read.”
    When King Sejong first invented the Korean letters, they had 28 letters, but only 24 are used today. All the Korean people enjoy  u____ their own letters. Some Chinese young people think they're interesting.