1.   Despite their promise, fuel cells still pose big hurdles, and they are likely to be confined to commercial fleets, at least initially.

2.   Distribution poses another hurdle for CD-ROM magazines.

3.   Financial turmoil abroad, perhaps the most significant business development of last year, also promises to pose continuing hurdles for big banks.

4.   However, concerns about safety pose a hurdle to testing such a vaccine in humans.

5.   In Congress, members of both parties keep returning to the problems of the uninsured, but the cost and complexity of the issue pose extraordinary hurdles.

6.   Long shifts pose other hurdles for night workers, like boredom during late-hour lulls, and the troublesome period before dawn.

7.   The narrow running board is useful only for the small-footed, but it sticks out so far it poses a hurdle.

8.   Two other practical problems pose bigger hurdles than the economy for advocates of statehood.

9.   Of course, scientific and political concerns pose huge hurdles to any plan to unleash a genetically altered insect into the wild.

10.   While praising moves to lower trade barriers, Annan said during a working session that technical barriers still pose formidable hurdles.