根据所给提示，完成句子，每空一词，含缩略词。

1. He has already finished his homework. (改否定句) 

    He ______ finished his homework _______.

2. The U.S.A had about 296 million people in 2005. (对划线部分提问)

    ______ the ______ of the U.S.A in 2005?

3. We must obey the school rules. (改为被动语态) 

    The school rules must ______  ______ by us.

4. I bought the pen six days ago. (同义句)

    ______  ______ six days since I bought the pen.

5. 我叔叔有时到上海出差.

    Sometimes my uncle go to Shanghai ______  ______.