adjunct  
noun [ C ] uk/ˈædʒ.ʌŋkt/ us/ˈædʒ.ʌŋkt/
  (SOMETHING ADDED)      
  formal附属物;附件 
something added or connected to a larger or more important thing
  I hoped I would find the computer course a useful adjunct to my other studies. 我希望学了这门计算机课程后,会使其他科目的学习如虎添翼。 
   (GRAMMAR)     
 language specialized修饰成分(语法中指在句子中提供附加信息的副词或者副词短语) 
In grammar, an adjunct is an adverb or phrase that gives extra information in a sentence.