阅读短文，从方框中选择适当的动词，并用其适当形式填空。有的需要加助动词或不定式符号(每词限用一次)。

    Jack, a British traveler and writer, has been exploring the Great Wall of China.

    When he was a small boy, he planned to explore the Great Wall, nobody  it seriously.

    But Jack achieved his goal. Now he in Beijing, and his new book,The  Great  WallExplained, out. There are a lot of photographs and articles. It is welcomed by the readers.

    It was a brave trip on the Great Wall and he had already run 3,000 kilometers along it!

    During those years, he got to many villages along the way. He by friendly villagers, although they didn't quite understand why the Englishman would have such interest in the Great Wall.