Choose a word from the Remember box and complete the sentences ( helpful, useful, hopeful, careful, helpless, useless, hopeless, careless).
1. You should be ... not to wake your baby sister.
2. Thank you for your advice. It was really ... .
3. John's grandfather says he cannot learn to text-message. He is .... .
4. If you are optimistic, you are ... .
5. You made a few mistakes. Try not to be so ... in the future.