11.   A number of researchers are therefore trying to tap straight into the nervous system, but that work remains at an early stage of development.

12.   Almost three months later, work remains at a standstill.

13.   Bud Selig, the acting commissioner, said Wednesday that much work remains to be done.

14.   But despite these steps, much work remains to be done.

15.   But given the large number of battered vacant buildings that cover the landscape, there is no way to hide the reality that much work remains to be done.

16.   But he said he endured the tragedy convinced that work remained to be done, and that his father would have wanted him to continue.

17.   But he emphasized that more work remained.

18.   But his work remains in obscurity.

19.   But how it would work remained as unclear as the hazy prospect of a coalition government.

20.   But if congressional approval depends on legisators like Markey, as Grossman says, then much work remains for proponents of advertisements on public television.