extra old特等陈年威士忌酒extraadj.额外的n.额外之物；临时演员adv.特别地extra-heavy crude oil超重原油extrapleural oleothorax胸膜外油胸ExtraceUular proteinase胞外蛋白酶extrachromosomal factor染色体外因子Extraterrestrial impact地外物体撞击extraterrestrial signal地外信号extrados springing line拱外弧起拱线extracellular chitinase胞外几丁质酶extraembryonic mesoderm胚外中胚层extrapolation technique外推法

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extra string to one's bow期望值存储器

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