求助:狒狒135的61题

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不妨取非，如果机械故障提高了50%，则机械故障报告的增多就并非“更严格的规则”，因而结论“That accounts for the fact that

reports of airplane mechanical problems have increased in frequency by 50 percent since last August.”不成立。呵呵，仅供参考哦