In Paragraph 3, the word "spikes" (in boldface) probably refers to ______.
A. the increases above the smog standard
B. the irregular readings about air quality in some areas
C. the occurrences of smog in Los Angeles
D. the current standards demanded by ALA
查看答案
【B17】
A. ways
B. methods
C. means
D. approaches
What basic problem are we told most trade unions face？
A. They are equal in size of influence.
B. They are less powerful than ever before.
C. They don't have enough members.
D. They are not organized efficiently.
资格考试合格的人员，取得《报检员资格证》。1年内未从事报检业务的，《报检员资格证》自动失效。
A. 正确
B. 错误
【B19】
A. free
B. retrieve
C. release
D. expose
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