1. Changes to the welfare system are the keystone of the government's reforms.

2. Keeping inflation low is the keystone of their economic policy.

3. The keystone of any personal injury case is medical evidence.

4. The keystones are richly carved and the arch soffit is deeply coffered and enriched.

5. Within families filial piety was the keystone of morality and it led logically to an absolute obedience to the household head.

6. A gourmet meal does await the adventurous at nearby Keystone Resort.

7. A dry stone conduit underlies the road here; a roadside marker is a metal keystone rusted blank.

8. In bureaucratic terms, Armstrong was the keystone in the arch of Heath's economic strategy from the autumn of 1972.

9. A high level of production has become a keystone of economic security.