Population/ world/ increase/ rapidly

1. Population/ world/ increase/ rapidly
2. Scientists/ work/ hard/ find/ alternative/ energy source/ because/ fossils fuels/ run out
3. young generation/ try/ independent/ parents/ soon/ possible
4. biogas/ aviilable/ abundant/ safe/ environment
5. People/ replace/ non- renewable/ renewable/ source/ energy/ sun/ wind/ water
Use the following words/ phrases to write complete sentences