文/ 甘编辑

Respectively 在科技论文中较常见，用以表示前一系列项目与后一系列项目按先后顺序一一对应的关系。

正确地使用 Respectively 这个词，往往能使得我们用更为简洁的语句来叙述一系列相关的内容。

例如：
  （1）不用 respectively：In mice treated with 5 mg/kg of the drug, the survival rate was 12%; whereas in mice treated with 10 mg/kg of the drug, the survival rate was 34%, and in mice treated with 20 mg/kg of the drug, the survival rate was 63%.

  （2）使用 respectively：In mice treated with 5 mg/kg, 10 mg/kg, and 20 mg/kg of the drug, the survival rates were 12%, 34%, and 57%, respectively.

上述两个句子都是正确的，但是句（2）中用了 respectively 这个词之后，显然比句子（1）更为简洁。

尽管使用 respectively 后能够简练句子，但有些句子却是不能够也不需要使用这个词的。譬如，当所叙述的项目与相应的数据放在一起叙述时，respectively 这个词就是多余的了。

例如：
  （3）错误：The complication rates were 14% in drinkers and 2% in non-drinkers, respectively.

  （4）正确：The complication rates were 14% in drinkers and 2% in non-drinkers. 

  （5）正确：The complication rates were 14% and 2% in drinkers and non-drinkers, respectively.

另外，叙述单一系列的内容时，不需要使用 respectively 这个词。使用 respectively 这个词的时候，前一系列的项目数量应该与后一系列所叙述的内容（结果）数量对应一致，且每一个系列都应单独逐个罗列，而不应该使用集合名词。

例如：
  （6）错误：The patients in the treatment group and the control group, respectively, underwent pre-operation chemotherapy. 

  （7）正确：The patients in the treatment group and the control group underwent pre-operation chemotherapy.

  （8）错误：The overall survival, disease-free survival, and prognosis-free survival rates of this cohort were 90.3% and 81.9%, respectively.

  （9）正确：The overall survival, disease-free survival, and prognosis-free survival rates of this cohort were 90.3%, 81.9%, and 81.9%, respectively.

  （10）错误：The overall survival rates of the two groups were 87.4% and 60.2%, respectively.

  （11）正确：The overall survival rates of the two groups were 87.4% and 60.2%.

  （12）正确：The overall survival rates of group A and group B were 87.4% and 60.2%, respectively.

参考文献
Hale K. Word for Word. Department of Scientific Publication of MD Anderson Cancer Center, Houston, TX, USA. 2018-04-11.
AMA Manual of Style, 10th ed. New York: Oxford University Press; 2007:401-402.
Burchfield RW, ed. The New Fowler's Modern English Usage, revised 3rd ed. New York: Oxford University Press; 2000:671-672.
Garner BA. Garner's Modern English Usage, 4th ed. New York: Oxford University Press; 2016:791.