第17题: [单项选择]The old lady has developed a ______ cough which cannot be cured completely in a short time. A. perpetual B. permanent C. chronic D. sustained 参考答案:C 答案解析:[句意] 那位女土得了慢性气管炎,短期内很难治愈。
[辨析] 近义词辨析。perpetual意为“持久的,永恒的”,指没有中断无限期的延续,常作定语,如:a treaty of perpetual