根据短文内容，用方框中所给单词的适当形式填空，每词限用一次。

    Hello! I'm Tina and this is Bob. He can help me with a lot of . Sometimes I ask him questions about my homework, and he can give me right answers. He can also help me do the heavy housework and  feels tired. He follows me everywhere. When I go out to do some he takes the shopping bag for me. He is really important in my life. I my robot could fly in the sky one day.