Help: 按首字母提示写词（英语）

Help: 按首字母提示写词（英语）
1. People can only drink and use n_______3% of water.
2. Of course, this little water is still e____ for us if no ore water is wanted and some of it can be t_____ back again.
3. Today more and more water is n_____ for more and more people.
4. A ________way is to use sea water b_____ moving the salt out.
5. M_______ in the end of the next century, there will be drinking water only.