In this task, you are given a sentence from the research paper and your task is to classify the given sentence into the following categories: Background (Why is this problem important? What relevant works have been created before? What is still missing in the previous works? What are the high-level research questions? How might this help other research or researchers?), Purpose (What specific things do the researchers want to do? What specific knowledge do the researchers want to gain? What specific hypothesis do the researchers want to test?), Method (How did the researchers do the work or find what they sought? What are the procedures and steps of the research?), or Finding (What did the researchers find out? Did the proposed methods work? Did the thing behave as the researchers expected?). 

Input: Consider Input: All patients had telephoned NHS Direct between 11 and 14 May with concerns about swine flu and had been assessed as being unlikely to have the illness.

Output: method


Input: Consider Input: 331 modern , high-standard , centralized facilities will be built up in China in municipal level cities.

Output: background


Input: Consider Input: Herein , we report on an intranasally administered biocompatible polyanhydride nanoparticle-based IAV vaccine ( IAV-nanovax ) capable of providing protection against subsequent homologous and heterologous IAV infections in both inbred and outbred populations.


Output: purpose