1. The recent medical breakthrough was the culmination of many long years of experimentation.

2. Magma is the primary source of all the earth’s rocks.

3. Saint Elmo’s Fire is a phenomenon that occurs when ships discharging harmless electrical charges into the atmosphere appear to shine.

4. Milk is purified by heating it at 60*C for thirty minutes.

5. Although monkeys occasionally menace their enemies, they are usually not dangerous unless they are provoked.

6. In the Navajo household, grandparents and other relatives play indispensable roles in raising the children.

7. Regular use of this cream will help to relieve the rough, dry condition of your skin.

8. Because leeches’ behavior patterns are simple, it is relatively easy to identify which neurons govern which behavior.

9. After the bottom fell out of the market, he was virtually bankrupt.

10. She didn’t say much, but her tone of voice insinuated more.

11. When calcium carbonate crystallizes from a solution, limestone is formed.

12. After receiving her check, Suzy endorsed it and took it to the bank.

13. The professor’s introductory remarks concerned the development of the laser beam.

14. The speaker was asked to condense his presentation in order to allow his audience to ask questions.

15. Immigrants entering the United States at the turn of the century often encountered living conditions radically different from those they had left behind.

16. Discretionary funds are included in most budgets to cover expenses that the contractor might run into during the work.

17. A nurse practitioner has training in a specialized area of medicine.

18. The United States government issues three types of passports: diplomatic, official, and regular.

19. Ice Age fossils from the La Brea tar pits in Los Angeles are now on display in the Natural History Museum in Los Angeles County.

20. The protesting crowd dispersed after the rally.