Complete the sentences with the words in the box. challenged - discoveries - overcome - investigating - contribution - covered - conservation - entrapment - maintained - migrate 1. Scientists have made many important new.................of the depth by using modern devices. 2. Community police have made a very positive ................to crime prevention. 3. This new discovery traditional beliefs. Some whales are known to.............into warm waters to bear their calves. 5. Seventy-five percent of the earth surface is .............by water. 6. Unless the biodiversity were.............marine life would be at stake. 7. Scientists are.....................how the crash occurred. 8. Sperm whale populations are at risk due to hunting and their accidental in ..............fishing nets. 9. What can I do to.................my fear of flying? 10. The government has just set up a wildlife....................project.