根据要求完成句子

1. He is too young to look after himself.(改为同义句)

    He is not _______ _______ to look after himself.

2. My parents allow me to stay up until 9:30 pm. (改为同义句)

    I _______ _______ to stay up until half _______ nine.

3. We can't decide when we should go to walk. (改为同义句)

    We can't decide _______ _______ go to school.

4. He walked so fast that I couldn't follow him. (改为同义句)

    He walked _______ fast _______ _______ _______ _______ him.

5. I have some ideas. It may help. (合并成一个句子)

    I have some ideas ________ ________ help.