sentence1: dependency parsing is the task of building dependency links between words in a sentence , which has recently gained a wide interest in the natural language processing community and has been used for many problems ranging from machine translation ( cite-p-12-1-4 ) to question answering ( zhou et al. , 2011a ) .
sentence2: dependency parsing is a crucial component of many natural language processing ( nlp ) systems for tasks such as relation extraction ( cite-p-15-1-5 ) , statistical machine translation ( cite-p-15-5-7 ) , text classification ( o ? zgu ? r and gu ? ngo ? r , 2010 ) , and question answering ( cite-p-15-3-0 ) .