Trình độ TOEFL - Bài 251. ________ thirteen states in the original United States.
2. Tuna, ________, may weigh up to 1,000 pounds.
3. ________ there is a close correlation between stress and illness.
4. ________ is often used in soups and sauces.
5. ________, common weedy plants with many-rayed yellow flowers, are more popular among children than among adults.
6. One of the professor's greatest attributes is ________.
7. ________ four major championships on the professional golf tour.
8. Progressive farmers use several methods to prevent top soil ________.
9. America's first globe maker was James Wilson, who ________ and blacksmith in his earlier life.
10. Albert Szent-Gyorgyi ________ the 1937 Nobel Prize for medicine for his synthesis of ascorbic acid.
11. ________ Social Security Act of 1935 was written to insure workers against unemployment.
12. The more she worked ________.
13. Having been selected to represent the Association of American Engineers at the International Convention, ________.
14. The decomposition of microscopic animals at the bottom of the sea results in an accumulation of ________ in porous rocks.
15. A perennial is ________ for more than two years, such as trees and shrubs.
16. Hybrids have one more ________ per plant than the other varieties.
17. Less moderate members of Congress are insisting that changes in the social security system ________ made.
18. The javelin used in competition must be between 260 and 270 centimeters ________
19. The closer to one of the earth's poles, the greater ________ gravitational force.
20. Pigs ________ certain characteristics with human beings.