1. 用方框中所给单词的适当形式填空，使短文完整正确。(每个单词限用一次，每空限填一个单词)。

begin,  happy,  success,  cry,  thousand,  good,  because,  use, sad, own

You have seen him all over the world, and there are of his fans. When you feel sad, see his warm smile and you'll be . It is Doraemon, a robot cat from the 22nd century.

Secret 1: Why does Doraemon always help Daxiong?

Doraemon helps Daxiong he is the great­great­great­great grandfather of Doraemon's in the 22nd century. Doraemon wants to help him become a man in the 21st century so that Doraemon's owner can have a life in the next century. To help him get the job done, Doraemon has a magic pocket filled with tools.

Secret 2: Why does Doraemon have blue skin?

It is a long story. In the , Doraemon's skin was yellow. One day, he lost his ears by accident and his girlfriend laughed at him. Doraemon felt and cried for a long time. When he stopped , he found that his yellow skin had turned blue.