1.   DNA tests proved that he was the father of the child.

2.   Independent tests have proved that Shell Advanced petrol will keep your engine three hundred percent cleaner than ordinary fuels.

3.   Tests have proved that the system works.

4.   The antibody test has proven invaluable as a means of protecting the blood supply.

5.   The tests proved the vaccine to be effective.

6.   Unfortunately, this test has proved somewhat difficult to apply to practical situations.

7.   An important point to note is that the existing theories are sometimes in conflict and the empirical tests have so far proved inconclusive.

8.   And if current tests prove successful they could also be used with liquids.

9.   Analysts believe the technical tests will prove successful, but its ultimate demand from print shops is unknown.

10.   An initial test proved positive for the bacteria.