根据句意及首字母提示写单词

1. Washing hands often is one of the best ways to p__________ the spread of H1N1 flu (H1N1型流感).

2. -Will Mr Wang come to our party?

    -I s__________ so.

3. Should students be allowed to use cell phones in school? The teacher organised a d__________

    about it last week.

4. Too much work and too little sleep usually cause(引起) i__________.

5. When you are ill, please take the m__________ as the doctor tells you.