24. Theof predator species and prey species is 1:5 in this park, which is an ideal balance in ecological communities.
A. pace
B. speed
C. ratio
D. rate
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25. The world’s population is aging. It is estimated that the people aged 60 or over will15% of the entire population by 2020.
A. consist
B. comprise
C. compose
D. include
26. He is planning another tour abroad, yet his passport willat the end of this month.
A. die
B. deadline
C. block
D. expire
27. Unemployment was the chief cause of.
A. property
B. poverty
C. wealth
D. fortune
28. The country is enjoying a period of peace and.
A. blaze
B. brilliance
C. prosperity
D. glory