Which of the following statements is TRUE？
American schools have not extended the school calendar mainly because of the objection from teachers and students.
B. The current American school calendar synchronizes work and family lives of Americans.
C. Long summer holidays do great harm to children's learning.
D. The United States has a shorter school calendar than most industrial nations.
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The author strongly implies that the animals which are easily saved from extinction are_____.
A. small and cute
B. dangerous to mankind
C. black and white
D. big,cute and vertebrate
Not until Kentucky's Mammoth Cave had been completely explored in 1972____.
A. when was its full extent realized
B. that its full extent realized
C. was its full extent realized
D. the realization of its full extent
【C6】
A. consoled
B. compacted
C. paid
D. bracketed
In the author's opinion,America's health system is____.
A. inefficient
B. feasible
C. unpopular
D. successful
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