The statement "College can be tough" is used to introduce______.
A. the severity of mental illnesses at college
B. the fierce competition of earning scholarships
C. the feeble relations between teachers and students
D. the anxiety of coping with all kinds of examinations
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目前，EAN 已将()分配给中国物品编码中心使用。
无论是核与辐射设施开展的自行监测，还是环境保护部门开展的监督性监测，在开展监测工作之前必须制定出切实可行的监测()。
A. 大纲
B. 计划
C. 文件
D. 预案
It can be inferred from the passage that ______.
A. war is one of the main causes of PTSD
B. extinction therapy involves moral issues
C. Gogolla often writes for the journal Science
D. fearful memories will recover spontaneously
在数据库中有表示 UPC-E 的 8 位代码吗？为什么？
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