13. Products which are made from dirts and are __________ high temperatures are known as ceramics.
A. tempered in B. subjected to
C. exposed to D. baked in
14. A pigment called melanin protects the ________ layers of skin from sun rays.
A. under B. below
C. underlying D. underneath

15. Oranges are a __________source of vitamin C.
A. well B. better
C. good D. very

16. Even after having their grandchildren live with them for ten years, the couple felt that __________ children these days was the most difficult of all family matters.
A. rising B. raising
C. caring D. taking care

17. The most important __________ of the farmers in Iraq is dates, of which Iraq is the world''s leading exporter.
A. economic crop B. cash crop
C. money crop D. staple

18. More has been learned about the Moon than any other of the Earth’s neighbors in space because of the Apollo program, which enabled men to walk on the Moon and bring back hundreds of pounds of __________.
A. rocks B. rock
C. stone D. stones

19. __________ the variety that the average family has in beaf, fish, poultry, and vegetarian recipes, they find most meals unexciting.
A. In spite B. Inspite
C. Despite of D. Despite

20. The speaker __________ have criticized the paraprofessionals, knowing full well that they were seated in the audience.
A. should not to B. must not
C. ought not to D. may not

上一页  [1] [2]