给定一篇英文文本，将其中的所有人名、地名和组织名提取出来。


The conference was held in Washington D.C. last week. Many important figures, including Prime Minister Johnson and Chairman Lee, attended the conference. The conference was organized by the United Nations and sponsored by ABC company.
Person names: Prime Minister Johnson, Chairman Lee.
Location names: Washington D.C.
Organization names: United Nations, ABC company.