阅读下面的材料，在空白处填入一个适当的词，或填入括号内所给单词的正确形式（每空最多不超过三个单词）

    A king had two sons and asked famous teachers to teach them. After a few (year), the king fell badly ill. So he wanted to choose one of his sons as the next king, but which one would be the right person? He thought it over a whole night. At last, he decided (test) his sons.

    One day, he gave a room to each of (they), You must fill the room completely (完全地) with anything you wish. But there should (be)no space left and you can't ask for advice from anyone!"

    The next day the king (visit) his elder son's room. The room was completely filled with grass. The king felt sorry about it. Then he went to other room, but it was closed. His (young) son asked him to get in and closed the door again. It was dark everywhere, so the king shouted at him (angry), But suddenly the second son lighted a candle and the room was full of light. The king felt very excited and hugged him proudly.

    He realized: Wisdom(智慧) is more important than simple answers are easy to get.