短語詞組短語background of the research 研究背景Project background research - 活動背景調(diào)研radiation background research 本底environmental radiation background research 環(huán)境本底Background of This Research 研究背景The Background of the Research 研究背景research background 研究背景Background information and theoretical research 理論調(diào)研Research Background and Significance 研究背景及意義;研究背景及重要意義;研究背景與意義 返回 background research