为预防碘缺乏，常在缺碘地区用碘化物强化食盐，碘加入量一般控制在()。
A. 1：(200～500)
B. 1：(2000~5000)
C. 1：(20000~50ooo)
D. 1：(200000500000)
E. 0．019／6～0．02％
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The student is afraid to answer the teacher‘s question.
A. hope
B. use
C. help
D. reply
The manager demanded that this job should be finished before next Monday.
A. required
B. cried
C. ordered
D. suggested
I want to provide my children with a decent education.
A. special
B. private
C. good
D. general
John is cooperating with Mary in writing an article.
A. working for
B. working out
C. working in
D. working with
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