11.   The scientists also believe that temperatures could rise far higher and faster than previously predicted if emissions are not curtailed.

12.   The scientists believed the reports.

13.   Scientists believe the disease can be conquered.

14.   Scientists now believe that the bones belong to a different species of reptile.

15.   Scientists believe the enormous crater was created by the impact of a meteorite thousands of years ago.

16.   About three million years ago, scientists believe, the first human beings walked the Earth.

17.   Until now, scientists believed that specialized cells could not be used to form a complete living thing.

18.   Scientists believe that if something is not done about this problem, glacial ice will melt raising the level of the sea and flooding vast areas of low-lying land.

19.   When Weismann first put it forward at the beginning of the century, it was highly controversial, and most scientists did not believe it.

20.   European Commission scientists believe that removal of the two chemicals will make the fuel more volatile.